**
*************************************************************************
** This file contains code used to implement the sqlite3_set_authorizer()
** API.  This facility is an optional feature of the library.  Embedded
** systems that do not need this facility may omit it by recompiling
** the library with -DSQLITE_OMIT_AUTHORIZATION=1
**
** $Id: auth.c,v 1.20 2005/01/22 03:03:54 drh Exp $
*/
#include "sqliteInt.h"

/*
** All of the code in this file may be omitted by defining a single
** macro.
*/
................................................................................
  const char *zCol;     /* Name of the column of the table */
  int iSrc;             /* Index in pTabList->a[] of table being read */
  const char *zDBase;   /* Name of database being accessed */
  TriggerStack *pStack; /* The stack of current triggers */

  if( db->xAuth==0 ) return;
  assert( pExpr->op==TK_COLUMN );
  for(iSrc=0; iSrc<pTabList->nSrc; iSrc++){
    if( pExpr->iTable==pTabList->a[iSrc].iCursor ) break;
  }
  if( iSrc>=0 && iSrc<pTabList->nSrc ){
    pTab = pTabList->a[iSrc].pTab;
  }else if( (pStack = pParse->trigStack)!=0 ){
    /* This must be an attempt to read the NEW or OLD pseudo-tables
    ** of a trigger.
    */
    assert( pExpr->iTable==pStack->newIdx || pExpr->iTable==pStack->oldIdx );
    pTab = pStack->pTab;

**
*************************************************************************
** This file contains code used to implement the sqlite3_set_authorizer()
** API.  This facility is an optional feature of the library.  Embedded
** systems that do not need this facility may omit it by recompiling
** the library with -DSQLITE_OMIT_AUTHORIZATION=1
**
** $Id: auth.c,v 1.21 2005/01/29 08:32:44 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** All of the code in this file may be omitted by defining a single
** macro.
*/
................................................................................
  const char *zCol;     /* Name of the column of the table */
  int iSrc;             /* Index in pTabList->a[] of table being read */
  const char *zDBase;   /* Name of database being accessed */
  TriggerStack *pStack; /* The stack of current triggers */

  if( db->xAuth==0 ) return;
  assert( pExpr->op==TK_COLUMN );
  for(iSrc=0; pTabList && iSrc<pTabList->nSrc; iSrc++){
    if( pExpr->iTable==pTabList->a[iSrc].iCursor ) break;
  }
  if( iSrc>=0 && pTabList && iSrc<pTabList->nSrc ){
    pTab = pTabList->a[iSrc].pTab;
  }else if( (pStack = pParse->trigStack)!=0 ){
    /* This must be an attempt to read the NEW or OLD pseudo-tables
    ** of a trigger.
    */
    assert( pExpr->iTable==pStack->newIdx || pExpr->iTable==pStack->oldIdx );
    pTab = pStack->pTab;

**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.300 2005/01/27 00:33:38 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** This routine is called when a new SQL statement is beginning to
** be parsed.  Initialize the pParse structure as needed.
................................................................................

  /* Get the VDBE program ready for execution
  */
  if( v && pParse->nErr==0 ){
    FILE *trace = (db->flags & SQLITE_VdbeTrace)!=0 ? stdout : 0;
    sqlite3VdbeTrace(v, trace);
    sqlite3VdbeMakeReady(v, pParse->nVar, pParse->nMem+3,
                         pParse->nTab+3, pParse->explain);
    pParse->rc = pParse->nErr ? SQLITE_ERROR : SQLITE_DONE;
    pParse->colNamesSet = 0;
  }else if( pParse->rc==SQLITE_OK ){
    pParse->rc = SQLITE_ERROR;
  }
  pParse->nTab = 0;
  pParse->nMem = 0;
  pParse->nSet = 0;
  pParse->nAgg = 0;
  pParse->nVar = 0;
  pParse->cookieMask = 0;
  pParse->cookieGoto = 0;
}

/*
** Run the parser and code generator recursively in order to generate
................................................................................
  pCol = &(p->aCol[p->nCol-1]);
  if( !sqlite3ExprIsConstant(pExpr) ){
    sqlite3ErrorMsg(pParse, "default value of column [%s] is not constant",
        pCol->zName);
  }else{
    sqlite3ExprDelete(pCol->pDflt);
    pCol->pDflt = sqlite3ExprDup(pExpr);
    sqlite3ExprResolveNames(pParse,0,0,0,pExpr,0,0);
  }
  sqlite3ExprDelete(pExpr);
}

/*
** Designate the PRIMARY KEY for the table.  pList is a list of names 
** of columns that form the primary key.  If pList is NULL, then the
................................................................................
    */
    if( pSelect ){
      Table *pSelTab;
      sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
      sqlite3VdbeAddOp(v, OP_Integer, p->iDb, 0);
      sqlite3VdbeAddOp(v, OP_OpenWrite, 1, 0);
      pParse->nTab = 2;
      sqlite3Select(pParse, pSelect, SRT_Table, 1, 0, 0, 0, 0, 0);
      sqlite3VdbeAddOp(v, OP_Close, 1, 0);
      if( pParse->nErr==0 ){
        pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSelect);
        if( pSelTab==0 ) return;
        assert( p->aCol==0 );
        p->nCol = pSelTab->nCol;
        p->aCol = pSelTab->aCol;

**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.301 2005/01/29 08:32:45 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** This routine is called when a new SQL statement is beginning to
** be parsed.  Initialize the pParse structure as needed.
................................................................................

  /* Get the VDBE program ready for execution
  */
  if( v && pParse->nErr==0 ){
    FILE *trace = (db->flags & SQLITE_VdbeTrace)!=0 ? stdout : 0;
    sqlite3VdbeTrace(v, trace);
    sqlite3VdbeMakeReady(v, pParse->nVar, pParse->nMem+3,
                         pParse->nTab+3, pParse->nMaxDepth+1, pParse->explain);
    pParse->rc = pParse->nErr ? SQLITE_ERROR : SQLITE_DONE;
    pParse->colNamesSet = 0;
  }else if( pParse->rc==SQLITE_OK ){
    pParse->rc = SQLITE_ERROR;
  }
  pParse->nTab = 0;
  pParse->nMem = 0;
  pParse->nSet = 0;

  pParse->nVar = 0;
  pParse->cookieMask = 0;
  pParse->cookieGoto = 0;
}

/*
** Run the parser and code generator recursively in order to generate
................................................................................
  pCol = &(p->aCol[p->nCol-1]);
  if( !sqlite3ExprIsConstant(pExpr) ){
    sqlite3ErrorMsg(pParse, "default value of column [%s] is not constant",
        pCol->zName);
  }else{
    sqlite3ExprDelete(pCol->pDflt);
    pCol->pDflt = sqlite3ExprDup(pExpr);

  }
  sqlite3ExprDelete(pExpr);
}

/*
** Designate the PRIMARY KEY for the table.  pList is a list of names 
** of columns that form the primary key.  If pList is NULL, then the
................................................................................
    */
    if( pSelect ){
      Table *pSelTab;
      sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
      sqlite3VdbeAddOp(v, OP_Integer, p->iDb, 0);
      sqlite3VdbeAddOp(v, OP_OpenWrite, 1, 0);
      pParse->nTab = 2;
      sqlite3Select(pParse, pSelect, SRT_Table, 1, 0, 0, 0, 0);
      sqlite3VdbeAddOp(v, OP_Close, 1, 0);
      if( pParse->nErr==0 ){
        pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSelect);
        if( pSelTab==0 ) return;
        assert( p->aCol==0 );
        p->nCol = pSelTab->nCol;
        p->aCol = pSelTab->aCol;

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** in order to generate code for DELETE FROM statements.
**
** $Id: delete.c,v 1.99 2005/01/20 11:32:24 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** Look up every table that is named in pSrc.  If any table is not found,
** add an error message to pParse->zErrMsg and return NULL.  If all tables
** are found, return a pointer to the last table.
................................................................................
  int i;                 /* Loop counter */
  WhereInfo *pWInfo;     /* Information about the WHERE clause */
  Index *pIdx;           /* For looping over indices of the table */
  int iCur;              /* VDBE Cursor number for pTab */
  sqlite3 *db;           /* Main database structure */
  AuthContext sContext;  /* Authorization context */
  int oldIdx = -1;       /* Cursor for the OLD table of AFTER triggers */


#ifndef SQLITE_OMIT_TRIGGER
  int isView;                  /* True if attempting to delete from a view */
  int triggers_exist = 0;      /* True if any triggers exist */
#endif

  sContext.pParse = 0;
................................................................................

  /* Allocate a cursor used to store the old.* data for a trigger.
  */
  if( triggers_exist ){ 
    oldIdx = pParse->nTab++;
  }

  /* Resolve the column names in all the expressions.
  */
  assert( pTabList->nSrc==1 );
  iCur = pTabList->a[0].iCursor = pParse->nTab++;



  if( sqlite3ExprResolveNames(pParse, pTabList, 0, 0, pWhere, 0, 1) ){
    goto delete_from_cleanup;
  }

  /* Start the view context
  */
  if( isView ){
    sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
................................................................................
  sqlite3BeginWriteOperation(pParse, triggers_exist, pTab->iDb);

  /* If we are trying to delete from a view, construct that view into
  ** a temporary table.
  */
  if( isView ){
    Select *pView = sqlite3SelectDup(pTab->pSelect);
    sqlite3Select(pParse, pView, SRT_TempTable, iCur, 0, 0, 0, 0, 0);
    sqlite3SelectDelete(pView);
  }

  /* Initialize the counter of the number of rows deleted, if
  ** we are counting rows.
  */
  if( db->flags & SQLITE_CountRows ){

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** in order to generate code for DELETE FROM statements.
**
** $Id: delete.c,v 1.100 2005/01/29 08:32:45 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** Look up every table that is named in pSrc.  If any table is not found,
** add an error message to pParse->zErrMsg and return NULL.  If all tables
** are found, return a pointer to the last table.
................................................................................
  int i;                 /* Loop counter */
  WhereInfo *pWInfo;     /* Information about the WHERE clause */
  Index *pIdx;           /* For looping over indices of the table */
  int iCur;              /* VDBE Cursor number for pTab */
  sqlite3 *db;           /* Main database structure */
  AuthContext sContext;  /* Authorization context */
  int oldIdx = -1;       /* Cursor for the OLD table of AFTER triggers */
  NameContext sNC;       /* Name context to resolve expressions in */

#ifndef SQLITE_OMIT_TRIGGER
  int isView;                  /* True if attempting to delete from a view */
  int triggers_exist = 0;      /* True if any triggers exist */
#endif

  sContext.pParse = 0;
................................................................................

  /* Allocate a cursor used to store the old.* data for a trigger.
  */
  if( triggers_exist ){ 
    oldIdx = pParse->nTab++;
  }

  /* Resolve the column names in the WHERE clause.
  */
  assert( pTabList->nSrc==1 );
  iCur = pTabList->a[0].iCursor = pParse->nTab++;
  memset(&sNC, 0, sizeof(sNC));
  sNC.pParse = pParse;
  sNC.pSrcList = pTabList;
  if( sqlite3ExprResolveNames(&sNC, pWhere) ){
    goto delete_from_cleanup;
  }

  /* Start the view context
  */
  if( isView ){
    sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
................................................................................
  sqlite3BeginWriteOperation(pParse, triggers_exist, pTab->iDb);

  /* If we are trying to delete from a view, construct that view into
  ** a temporary table.
  */
  if( isView ){
    Select *pView = sqlite3SelectDup(pTab->pSelect);
    sqlite3Select(pParse, pView, SRT_TempTable, iCur, 0, 0, 0, 0);
    sqlite3SelectDelete(pView);
  }

  /* Initialize the counter of the number of rows deleted, if
  ** we are counting rows.
  */
  if( db->flags & SQLITE_CountRows ){

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.188 2005/01/23 22:41:37 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**
................................................................................
  pNew->pPrior = sqlite3SelectDup(p->pPrior);
  pNew->nLimit = p->nLimit;
  pNew->nOffset = p->nOffset;
  pNew->iLimit = -1;
  pNew->iOffset = -1;
  pNew->ppOpenTemp = 0;
  pNew->pFetch = 0;


  return pNew;
}
#else
Select *sqlite3SelectDup(Select *p){
  assert( p==0 );
  return 0;
}
................................................................................
  pExpr->iTable = -1;
  while( pNC && cnt==0 ){
    SrcList *pSrcList = pNC->pSrcList;
    ExprList *pEList = pNC->pEList;

    pNC->nRef++;
    /* assert( zTab==0 || pEList==0 ); */

    for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){
      Table *pTab = pItem->pTab;
      Column *pCol;

      if( pTab==0 ) continue;
      assert( pTab->nCol>0 );
      if( zTab ){
        if( pItem->zAlias ){
          char *zTabName = pItem->zAlias;
          if( sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
        }else{
          char *zTabName = pTab->zName;
          if( zTabName==0 || sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
          if( zDb!=0 && sqlite3StrICmp(db->aDb[pTab->iDb].zName, zDb)!=0 ){
            continue;
          }
        }
      }
      if( 0==(cntTab++) ){
        pExpr->iTable = pItem->iCursor;
        pExpr->iDb = pTab->iDb;
        pMatch = pItem;
      }
      for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){
        if( sqlite3StrICmp(pCol->zName, zCol)==0 ){
          cnt++;
          pExpr->iTable = pItem->iCursor;
          pMatch = pItem;
          pExpr->iDb = pTab->iDb;
          /* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */
          pExpr->iColumn = j==pTab->iPKey ? -1 : j;
          pExpr->affinity = pTab->aCol[j].affinity;
          pExpr->pColl = pTab->aCol[j].pColl;
          break;

        }
      }
    }

#ifndef SQLITE_OMIT_TRIGGER
    /* If we have not already resolved the name, then maybe 
    ** it is a new.* or old.* trigger argument reference
................................................................................
  sqliteFree(zCol);
  sqlite3ExprDelete(pExpr->pLeft);
  pExpr->pLeft = 0;
  sqlite3ExprDelete(pExpr->pRight);
  pExpr->pRight = 0;
  pExpr->op = TK_COLUMN;
  if( cnt==1 ){
    assert( pNC!=0 && pNC->pSrcList!=0 );
    sqlite3AuthRead(pParse, pExpr, pNC->pSrcList);
  }
  return cnt!=1;
}

/*
** pExpr is a node that defines a function of some kind.  It might
................................................................................
** to TK_AGG_FUNCTION.
*/
static int nameResolverStep(void *pArg, Expr *pExpr){
  NameContext *pNC = (NameContext*)pArg;
  SrcList *pSrcList;
  Parse *pParse;


  assert( pNC!=0 );
  pSrcList = pNC->pSrcList;
  pParse = pNC->pParse;
  if( pExpr==0 ) return 1;
  if( ExprHasAnyProperty(pExpr, EP_Resolved) ) return 1;
  ExprSetProperty(pExpr, EP_Resolved);
#ifndef NDEBUG
  if( pSrcList ){
    int i;
    for(i=0; i<pSrcList->nSrc; i++){
      assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab);
................................................................................
    case TK_STRING: {
      if( pExpr->token.z[0]=='\'' ) break;
      /* Fall thru into the TK_ID case if this is a double-quoted string */
    }
    /* A lone identifier is the name of a column.
    */
    case TK_ID: {
      if( pSrcList==0 ) break;
      lookupName(pParse, 0, 0, &pExpr->token, pNC, pExpr);
      return 1;
    }
  
    /* A table name and column name:     ID.ID
    ** Or a database, table and column:  ID.ID.ID
    */
    case TK_DOT: {
      Token *pColumn;
      Token *pTable;
      Token *pDb;
      Expr *pRight;

      if( pSrcList==0 ) break;
      pRight = pExpr->pRight;
      if( pRight->op==TK_ID ){
        pDb = 0;
        pTable = &pExpr->pLeft->token;
        pColumn = &pRight->token;
      }else{
        assert( pRight->op==TK_DOT );
................................................................................
    }

    /* Resolve function names
    */
    case TK_CTIME:
    case TK_CTIMESTAMP:
    case TK_CDATE:
    /* Note: The above three were a seperate case in sqlmoto. Reason? */
    case TK_GLOB:
    case TK_LIKE:
    case TK_FUNCTION: {
      ExprList *pList = pExpr->pList;    /* The argument list */
      int n = pList ? pList->nExpr : 0;  /* Number of arguments */
      int no_such_func = 0;       /* True if no such function exists */
      int wrong_num_args = 0;     /* True if wrong number of arguments */
................................................................................
      }
      if( is_agg ) pNC->allowAgg = 1;
      /* FIX ME:  Compute pExpr->affinity based on the expected return
      ** type of the function 
      */
      return is_agg;
    }














  }
  return 0;
}

/* Forward declaration */
static int sqlite3ExprCodeSubquery(Parse*, NameContext*, Expr*);

/*
** This routine walks an expression tree and resolves references to
** table columns.  Nodes of the form ID.ID or ID resolve into an
** index to the table in the table list and a column offset.  The 
** Expr.opcode for such nodes is changed to TK_COLUMN.  The Expr.iTable
** value is changed to the index of the referenced table in pTabList
** plus the "base" value.  The base value will ultimately become the
................................................................................
** have the correct number of arguments.  Leave an error message
** in pParse->zErrMsg if anything is amiss.  Return the number of errors.
**
** If the expression contains aggregate functions then set the EP_Agg
** property on the expression.
*/
int sqlite3ExprResolveNames(
  Parse *pParse,          /* The parser context */
  SrcList *pSrcList,      /* List of tables used to resolve column names */
  ExprList *pEList,       /* List of expressions used to resolve "AS" */
  NameContext *pNC,       /* Namespace of enclosing statement */
  Expr *pExpr,            /* The expression to be analyzed. */
  int allowAgg,           /* True to allow aggregate expressions */
  int codeSubquery        /* If true, then generate code for subqueries too */
){
  NameContext sNC;

  if( pExpr==0 ) return 0;
  memset(&sNC, 0, sizeof(sNC));
  sNC.pSrcList = pSrcList;
  sNC.pParse = pParse;
  sNC.pEList = pEList;
  sNC.allowAgg = allowAgg;
  sNC.pNext = pNC;
  walkExprTree(pExpr, nameResolverStep, &sNC);
  if( sNC.hasAgg ){
    ExprSetProperty(pExpr, EP_Agg);
  }
  if( sNC.nErr>0 ){
    ExprSetProperty(pExpr, EP_Error);
  }else if( codeSubquery  && sqlite3ExprCodeSubquery(pParse, &sNC, pExpr) ){
    return 1;
  }
  return ExprHasProperty(pExpr, EP_Error);
}

/*
** A pointer instance of this structure is used to pass information
** through walkExprTree into codeSubqueryStep().
................................................................................
**           expr IN (exprlist)
** and
**           expr IN (SELECT ...)
**
** The first form is handled by creating a set holding the list
** of allowed values.  The second form causes the SELECT to generate 
** a temporary table.
**
** This routine also looks for scalar SELECTs that are part of an expression.
** If it finds any, it generates code to write the value of that select
** into a memory cell.
**
** This routine is a callback for wallExprTree() used to implement
** sqlite3ExprCodeSubquery().  See comments on those routines for
** additional information.
*/
#ifndef SQLITE_OMIT_SUBQUERY








static int codeSubqueryStep(void *pArg, Expr *pExpr){
  QueryCoder *pCoder = (QueryCoder*)pArg;
  Parse *pParse = pCoder->pParse;











  switch( pExpr->op ){
    case TK_IN: {
      char affinity;
      Vdbe *v = sqlite3GetVdbe(pParse);
      KeyInfo keyInfo;
      int addr;        /* Address of OP_OpenTemp instruction */

      if( v==0 ) return 2;
      affinity = sqlite3ExprAffinity(pExpr->pLeft);

      /* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
      ** expression it is handled the same way. A temporary table is 
      ** filled with single-field index keys representing the results
      ** from the SELECT or the <exprlist>.
      **
................................................................................
        **
        ** Generate code to write the results of the select into the temporary
        ** table allocated and opened above.
        */
        int iParm = pExpr->iTable +  (((int)affinity)<<16);
        ExprList *pEList;
        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
        sqlite3Select(pParse, pExpr->pSelect, SRT_Set, iParm, 0, 0, 0, 0, 0);
        pEList = pExpr->pSelect->pEList;
        if( pEList && pEList->nExpr>0 ){ 
          keyInfo.aColl[0] = binaryCompareCollSeq(pParse, pExpr->pLeft,
              pEList->a[0].pExpr);
        }
      }else if( pExpr->pList ){
        /* Case 2:     expr IN (exprlist)
................................................................................
        for(i=0; i<pExpr->pList->nExpr; i++){
          Expr *pE2 = pExpr->pList->a[i].pExpr;

          /* Check that the expression is constant and valid. */
          if( !sqlite3ExprIsConstant(pE2) ){
            sqlite3ErrorMsg(pParse,
              "right-hand side of IN operator must be constant");
            return 2;
          }
          if( sqlite3ExprResolveNames(pParse, 0, 0, 0, pE2, 0, 0) ){
            return 2;
          }

          /* Evaluate the expression and insert it into the temp table */
          sqlite3ExprCode(pParse, pE2);
          sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, &affinity, 1);
          sqlite3VdbeAddOp(v, OP_String8, 0, 0);
          sqlite3VdbeAddOp(v, OP_PutStrKey, pExpr->iTable, 0);
        }
      }
      sqlite3VdbeChangeP3(v, addr, (void *)&keyInfo, P3_KEYINFO);
      return 1;
    }

    case TK_EXISTS:
    case TK_SELECT: {
      /* This has to be a scalar SELECT.  Generate code to put the
      ** value of this select in a memory cell and record the number
      ** of the memory cell in iColumn.
      */
      NameContext *pNC;
      int nRef;
      Vdbe *v;
      int addr;
      int sop;
      Select *pSel;

      pNC = pCoder->pNC;
      if( pNC ) nRef = pNC->nRef;
      sqlite3CodeVerifySchema(pParse, -1); /* Insert the cookie verifier Goto */
      v = sqlite3GetVdbe(pParse);
      addr = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
      pExpr->iColumn = pParse->nMem++;
      pSel = pExpr->pSelect;
      if( pExpr->op==TK_SELECT ){
        sop = SRT_Mem;
      }else{
        static const Token one = { "1", 0, 1 };
        sop = SRT_Exists;
        sqlite3ExprListDelete(pSel->pEList);
        pSel->pEList = sqlite3ExprListAppend(0, 
                          sqlite3Expr(TK_INTEGER, 0, 0, &one), 0);
      }
      sqlite3Select(pParse, pSel, sop, pExpr->iColumn, 0, 0, 0, 0, pNC);
      if( pNC && pNC->nRef>nRef ){
        /* Subquery value changes.  Evaluate at each use */
        pExpr->iTable = addr+1;
        sqlite3VdbeAddOp(v, OP_Return, 0, 0);
        sqlite3VdbeChangeP2(v, addr, sqlite3VdbeCurrentAddr(v));
      }else{
        /* Subquery value is constant.  evaluate only once. */
        pExpr->iTable = -1;
        sqlite3VdbeChangeP2(v, addr, addr+1);
      }
      return 1;
    }
  }
  return 0;


}
#endif /* SQLITE_OMIT_SUBQUERY */



/*
** Generate code to evaluate subqueries and IN operators contained
** in expression pExpr.
*/
static int sqlite3ExprCodeSubquery(
  Parse *pParse,       /* Parser */
  NameContext *pNC,    /* First enclosing namespace.  Often NULL */
  Expr *pExpr          /* Subquery to be coded */
){
#ifndef SQLITE_OMIT_SUBQUERY
  QueryCoder sCoder;
  sCoder.pParse = pParse;
  sCoder.pNC = pNC;
  walkExprTree(pExpr, codeSubqueryStep, &sCoder);
#endif
  return 0;
}


/*
** Generate an instruction that will put the integer describe by
** text z[0..n-1] on the stack.
*/
static void codeInteger(Vdbe *v, const char *z, int n){
  int i;
  if( sqlite3GetInt32(z, &i) ){
................................................................................
      }
      sqlite3VdbeOp3(v, OP_Function, nExpr, p2, (char*)pDef, P3_FUNCDEF);
      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case TK_EXISTS:
    case TK_SELECT: {
      if( pExpr->iTable>=0 ){
        sqlite3VdbeAddOp(v, OP_Gosub, 0, pExpr->iTable);
        VdbeComment((v, "# run subquery"));
      }
      sqlite3VdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);
      VdbeComment((v, "# load subquery result"));
      break;
    }
    case TK_IN: {
      int addr;
      char affinity;


      /* Figure out the affinity to use to create a key from the results
      ** of the expression. affinityStr stores a static string suitable for
      ** P3 of OP_MakeRecord.
      */
      affinity = comparisonAffinity(pExpr);

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.189 2005/01/29 08:32:45 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**
................................................................................
  pNew->pPrior = sqlite3SelectDup(p->pPrior);
  pNew->nLimit = p->nLimit;
  pNew->nOffset = p->nOffset;
  pNew->iLimit = -1;
  pNew->iOffset = -1;
  pNew->ppOpenTemp = 0;
  pNew->pFetch = 0;
  pNew->isResolved = 0;
  pNew->isAgg = 0;
  return pNew;
}
#else
Select *sqlite3SelectDup(Select *p){
  assert( p==0 );
  return 0;
}
................................................................................
  pExpr->iTable = -1;
  while( pNC && cnt==0 ){
    SrcList *pSrcList = pNC->pSrcList;
    ExprList *pEList = pNC->pEList;

    pNC->nRef++;
    /* assert( zTab==0 || pEList==0 ); */
    if( pSrcList ){
      for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){
        Table *pTab = pItem->pTab;
        Column *pCol;
  
        if( pTab==0 ) continue;
        assert( pTab->nCol>0 );
        if( zTab ){
          if( pItem->zAlias ){
            char *zTabName = pItem->zAlias;
            if( sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
          }else{
            char *zTabName = pTab->zName;
            if( zTabName==0 || sqlite3StrICmp(zTabName, zTab)!=0 ) continue;
            if( zDb!=0 && sqlite3StrICmp(db->aDb[pTab->iDb].zName, zDb)!=0 ){
              continue;
            }
          }
        }
        if( 0==(cntTab++) ){
          pExpr->iTable = pItem->iCursor;
          pExpr->iDb = pTab->iDb;
          pMatch = pItem;
        }
        for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){
          if( sqlite3StrICmp(pCol->zName, zCol)==0 ){
            cnt++;
            pExpr->iTable = pItem->iCursor;
            pMatch = pItem;
            pExpr->iDb = pTab->iDb;
            /* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */
            pExpr->iColumn = j==pTab->iPKey ? -1 : j;
            pExpr->affinity = pTab->aCol[j].affinity;
            pExpr->pColl = pTab->aCol[j].pColl;
            break;
          }
        }
      }
    }

#ifndef SQLITE_OMIT_TRIGGER
    /* If we have not already resolved the name, then maybe 
    ** it is a new.* or old.* trigger argument reference
................................................................................
  sqliteFree(zCol);
  sqlite3ExprDelete(pExpr->pLeft);
  pExpr->pLeft = 0;
  sqlite3ExprDelete(pExpr->pRight);
  pExpr->pRight = 0;
  pExpr->op = TK_COLUMN;
  if( cnt==1 ){
    assert( pNC!=0 );
    sqlite3AuthRead(pParse, pExpr, pNC->pSrcList);
  }
  return cnt!=1;
}

/*
** pExpr is a node that defines a function of some kind.  It might
................................................................................
** to TK_AGG_FUNCTION.
*/
static int nameResolverStep(void *pArg, Expr *pExpr){
  NameContext *pNC = (NameContext*)pArg;
  SrcList *pSrcList;
  Parse *pParse;

  if( pExpr==0 ) return 1;
  assert( pNC!=0 );
  pSrcList = pNC->pSrcList;
  pParse = pNC->pParse;

  if( ExprHasAnyProperty(pExpr, EP_Resolved) ) return 1;
  ExprSetProperty(pExpr, EP_Resolved);
#ifndef NDEBUG
  if( pSrcList ){
    int i;
    for(i=0; i<pSrcList->nSrc; i++){
      assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab);
................................................................................
    case TK_STRING: {
      if( pExpr->token.z[0]=='\'' ) break;
      /* Fall thru into the TK_ID case if this is a double-quoted string */
    }
    /* A lone identifier is the name of a column.
    */
    case TK_ID: {

      lookupName(pParse, 0, 0, &pExpr->token, pNC, pExpr);
      return 1;
    }
  
    /* A table name and column name:     ID.ID
    ** Or a database, table and column:  ID.ID.ID
    */
    case TK_DOT: {
      Token *pColumn;
      Token *pTable;
      Token *pDb;
      Expr *pRight;

      /* if( pSrcList==0 ) break; */
      pRight = pExpr->pRight;
      if( pRight->op==TK_ID ){
        pDb = 0;
        pTable = &pExpr->pLeft->token;
        pColumn = &pRight->token;
      }else{
        assert( pRight->op==TK_DOT );
................................................................................
    }

    /* Resolve function names
    */
    case TK_CTIME:
    case TK_CTIMESTAMP:
    case TK_CDATE:

    case TK_GLOB:
    case TK_LIKE:
    case TK_FUNCTION: {
      ExprList *pList = pExpr->pList;    /* The argument list */
      int n = pList ? pList->nExpr : 0;  /* Number of arguments */
      int no_such_func = 0;       /* True if no such function exists */
      int wrong_num_args = 0;     /* True if wrong number of arguments */
................................................................................
      }
      if( is_agg ) pNC->allowAgg = 1;
      /* FIX ME:  Compute pExpr->affinity based on the expected return
      ** type of the function 
      */
      return is_agg;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case TK_SELECT:
    case TK_EXISTS:
#endif
    case TK_IN: {
      if( pExpr->pSelect ){
        int nRef = pNC->nRef;
        sqlite3SelectResolve(pParse, pExpr->pSelect, pNC);
        assert( pNC->nRef>=nRef );
        if( nRef!=pNC->nRef ){
          ExprSetProperty(pExpr, EP_VarSelect);
        }
      }
    }
  }
  return 0;
}




/*
** This routine walks an expression tree and resolves references to
** table columns.  Nodes of the form ID.ID or ID resolve into an
** index to the table in the table list and a column offset.  The 
** Expr.opcode for such nodes is changed to TK_COLUMN.  The Expr.iTable
** value is changed to the index of the referenced table in pTabList
** plus the "base" value.  The base value will ultimately become the
................................................................................
** have the correct number of arguments.  Leave an error message
** in pParse->zErrMsg if anything is amiss.  Return the number of errors.
**
** If the expression contains aggregate functions then set the EP_Agg
** property on the expression.
*/
int sqlite3ExprResolveNames(



  NameContext *pNC,       /* Namespace to resolve expressions in. */
  Expr *pExpr             /* The expression to be analyzed. */


){


  if( pExpr==0 ) return 0;






  walkExprTree(pExpr, nameResolverStep, pNC);



  if( pNC->nErr>0 ){
    ExprSetProperty(pExpr, EP_Error);


  }
  return ExprHasProperty(pExpr, EP_Error);
}

/*
** A pointer instance of this structure is used to pass information
** through walkExprTree into codeSubqueryStep().
................................................................................
**           expr IN (exprlist)
** and
**           expr IN (SELECT ...)
**
** The first form is handled by creating a set holding the list
** of allowed values.  The second form causes the SELECT to generate 
** a temporary table.








*/
#ifndef SQLITE_OMIT_SUBQUERY
void sqlite3CodeSubselect(Parse *pParse, Expr *pExpr){
  int label = 0;                         /* Address after sub-select code */
  Vdbe *v = sqlite3GetVdbe(pParse);
  if( v==0 ) return;

  /* If this is not a variable (correlated) select, then execute
  ** it only once. Unless this is part of a trigger program. In
  ** that case re-execute every time (this could be optimized).
  */
  if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){
    int mem = pParse->nMem++;
    sqlite3VdbeAddOp(v, OP_MemLoad, mem, 0);
    label = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp(v, OP_If, 0, label);
    sqlite3VdbeAddOp(v, OP_Integer, 1, 0);
    sqlite3VdbeAddOp(v, OP_MemStore, mem, 1);
  }

  if( pExpr->pSelect ){
    sqlite3VdbeAddOp(v, OP_AggContextPush, 0, 0);
  }

  switch( pExpr->op ){
    case TK_IN: {
      char affinity;

      KeyInfo keyInfo;
      int addr;        /* Address of OP_OpenTemp instruction */


      affinity = sqlite3ExprAffinity(pExpr->pLeft);

      /* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)'
      ** expression it is handled the same way. A temporary table is 
      ** filled with single-field index keys representing the results
      ** from the SELECT or the <exprlist>.
      **
................................................................................
        **
        ** Generate code to write the results of the select into the temporary
        ** table allocated and opened above.
        */
        int iParm = pExpr->iTable +  (((int)affinity)<<16);
        ExprList *pEList;
        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
        sqlite3Select(pParse, pExpr->pSelect, SRT_Set, iParm, 0, 0, 0, 0);
        pEList = pExpr->pSelect->pEList;
        if( pEList && pEList->nExpr>0 ){ 
          keyInfo.aColl[0] = binaryCompareCollSeq(pParse, pExpr->pLeft,
              pEList->a[0].pExpr);
        }
      }else if( pExpr->pList ){
        /* Case 2:     expr IN (exprlist)
................................................................................
        for(i=0; i<pExpr->pList->nExpr; i++){
          Expr *pE2 = pExpr->pList->a[i].pExpr;

          /* Check that the expression is constant and valid. */
          if( !sqlite3ExprIsConstant(pE2) ){
            sqlite3ErrorMsg(pParse,
              "right-hand side of IN operator must be constant");
            return;



          }

          /* Evaluate the expression and insert it into the temp table */
          sqlite3ExprCode(pParse, pE2);
          sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, &affinity, 1);
          sqlite3VdbeAddOp(v, OP_String8, 0, 0);
          sqlite3VdbeAddOp(v, OP_PutStrKey, pExpr->iTable, 0);
        }
      }
      sqlite3VdbeChangeP3(v, addr, (void *)&keyInfo, P3_KEYINFO);
      break;
    }

    case TK_EXISTS:
    case TK_SELECT: {
      /* This has to be a scalar SELECT.  Generate code to put the
      ** value of this select in a memory cell and record the number
      ** of the memory cell in iColumn.
      */




      int sop;
      Select *pSel;






      pExpr->iColumn = pParse->nMem++;
      pSel = pExpr->pSelect;
      if( pExpr->op==TK_SELECT ){
        sop = SRT_Mem;
      }else{
        static const Token one = { "1", 0, 1 };
        sop = SRT_Exists;
        sqlite3ExprListDelete(pSel->pEList);
        pSel->pEList = sqlite3ExprListAppend(0, 
                          sqlite3Expr(TK_INTEGER, 0, 0, &one), 0);
      }
      sqlite3Select(pParse, pSel, sop, pExpr->iColumn, 0, 0, 0, 0);
      break;








    }

  }


  if( pExpr->pSelect ){
    sqlite3VdbeAddOp(v, OP_AggContextPop, 0, 0);
  }

  if( label<0 ){
    sqlite3VdbeResolveLabel(v, label);
  }















  return;
}
#endif /* SQLITE_OMIT_SUBQUERY */

/*
** Generate an instruction that will put the integer describe by
** text z[0..n-1] on the stack.
*/
static void codeInteger(Vdbe *v, const char *z, int n){
  int i;
  if( sqlite3GetInt32(z, &i) ){
................................................................................
      }
      sqlite3VdbeOp3(v, OP_Function, nExpr, p2, (char*)pDef, P3_FUNCDEF);
      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case TK_EXISTS:
    case TK_SELECT: {
      sqlite3CodeSubselect(pParse, pExpr);



      sqlite3VdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);
      VdbeComment((v, "# load subquery result"));
      break;
    }
    case TK_IN: {
      int addr;
      char affinity;
      sqlite3CodeSubselect(pParse, pExpr);

      /* Figure out the affinity to use to create a key from the results
      ** of the expression. affinityStr stores a static string suitable for
      ** P3 of OP_MakeRecord.
      */
      affinity = comparisonAffinity(pExpr);

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle INSERT statements in SQLite.
**
** $Id: insert.c,v 1.134 2005/01/20 11:32:24 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** Set P3 of the most recently inserted opcode to a column affinity
** string for index pIdx. A column affinity string has one character
** for each column in the table, according to the affinity of the column:
................................................................................
  if( pSelect ){
    /* Data is coming from a SELECT.  Generate code to implement that SELECT
    */
    int rc, iInitCode;
    iInitCode = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
    iSelectLoop = sqlite3VdbeCurrentAddr(v);
    iInsertBlock = sqlite3VdbeMakeLabel(v);


    rc = sqlite3Select(pParse, pSelect, SRT_Subroutine, iInsertBlock,0,0,0,0,0);
    if( rc || pParse->nErr || sqlite3_malloc_failed ) goto insert_cleanup;

    iCleanup = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp(v, OP_Goto, 0, iCleanup);
    assert( pSelect->pEList );
    nColumn = pSelect->pEList->nExpr;

    /* Set useTempTable to TRUE if the result of the SELECT statement
    ** should be written into a temporary table.  Set to FALSE if each
................................................................................
    }else{
      sqlite3VdbeChangeP2(v, iInitCode, sqlite3VdbeCurrentAddr(v));
    }
  }else{
    /* This is the case if the data for the INSERT is coming from a VALUES
    ** clause
    */
    SrcList dummy;


    assert( pList!=0 );
    srcTab = -1;
    useTempTable = 0;
    assert( pList );
    nColumn = pList->nExpr;
    dummy.nSrc = 0;
    for(i=0; i<nColumn; i++){
      if( sqlite3ExprResolveNames(pParse,&dummy,0,0,pList->a[i].pExpr,0,1) ){
        goto insert_cleanup;
      }
    }
  }

  /* Make sure the number of columns in the source data matches the number
  ** of columns to be inserted into the table.

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle INSERT statements in SQLite.
**
** $Id: insert.c,v 1.135 2005/01/29 08:32:45 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** Set P3 of the most recently inserted opcode to a column affinity
** string for index pIdx. A column affinity string has one character
** for each column in the table, according to the affinity of the column:
................................................................................
  if( pSelect ){
    /* Data is coming from a SELECT.  Generate code to implement that SELECT
    */
    int rc, iInitCode;
    iInitCode = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
    iSelectLoop = sqlite3VdbeCurrentAddr(v);
    iInsertBlock = sqlite3VdbeMakeLabel(v);

    /* Resolve the expressions in the SELECT statement and execute it. */
    rc = sqlite3Select(pParse, pSelect, SRT_Subroutine, iInsertBlock,0,0,0,0);
    if( rc || pParse->nErr || sqlite3_malloc_failed ) goto insert_cleanup;

    iCleanup = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp(v, OP_Goto, 0, iCleanup);
    assert( pSelect->pEList );
    nColumn = pSelect->pEList->nExpr;

    /* Set useTempTable to TRUE if the result of the SELECT statement
    ** should be written into a temporary table.  Set to FALSE if each
................................................................................
    }else{
      sqlite3VdbeChangeP2(v, iInitCode, sqlite3VdbeCurrentAddr(v));
    }
  }else{
    /* This is the case if the data for the INSERT is coming from a VALUES
    ** clause
    */
    NameContext sNC;
    memset(&sNC, 0, sizeof(sNC));
    sNC.pParse = pParse;
    assert( pList!=0 );
    srcTab = -1;
    useTempTable = 0;
    assert( pList );
    nColumn = pList->nExpr;

    for(i=0; i<nColumn; i++){
      if( sqlite3ExprResolveNames(&sNC, pList->a[i].pExpr) ){
        goto insert_cleanup;
      }
    }
  }

  /* Make sure the number of columns in the source data matches the number
  ** of columns to be inserted into the table.

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.275 2005/01/25 04:27:55 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** The following constant value is used by the SQLITE_BIGENDIAN and
................................................................................
*/
int sqlite3_reset(sqlite3_stmt *pStmt){
  int rc;
  if( pStmt==0 ){
    rc = SQLITE_OK;
  }else{
    rc = sqlite3VdbeReset((Vdbe*)pStmt);
    sqlite3VdbeMakeReady((Vdbe*)pStmt, -1, 0, 0, 0);
  }
  return rc;
}

/*
** Register a new collation sequence with the database handle db.
*/

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.276 2005/01/29 08:32:45 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** The following constant value is used by the SQLITE_BIGENDIAN and
................................................................................
*/
int sqlite3_reset(sqlite3_stmt *pStmt){
  int rc;
  if( pStmt==0 ){
    rc = SQLITE_OK;
  }else{
    rc = sqlite3VdbeReset((Vdbe*)pStmt);
    sqlite3VdbeMakeReady((Vdbe*)pStmt, -1, 0, 0, 0, 0);
  }
  return rc;
}

/*
** Register a new collation sequence with the database handle db.
*/

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.186 2005/01/22 03:39:39 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>

................................................................................
*/
int sqlite3pager_close(Pager *pPager){
  PgHdr *pPg, *pNext;
  switch( pPager->state ){
    case PAGER_RESERVED:
    case PAGER_SYNCED: 
    case PAGER_EXCLUSIVE: {









      sqlite3pager_rollback(pPager);



      if( !MEMDB ){
        sqlite3OsUnlock(&pPager->fd, NO_LOCK);
      }
      assert( pPager->journalOpen==0 );
      break;
    }
    case PAGER_SHARED: {

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.187 2005/01/29 08:32:45 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>

................................................................................
*/
int sqlite3pager_close(Pager *pPager){
  PgHdr *pPg, *pNext;
  switch( pPager->state ){
    case PAGER_RESERVED:
    case PAGER_SYNCED: 
    case PAGER_EXCLUSIVE: {
      /* We ignore any IO errors that occur during the rollback
      ** operation. So disable IO error simulation so that testing
      ** works more easily.
      */
#if defined(SQLITE_TEST) && (defined(OS_UNIX) || defined(OS_WIN))
      extern int sqlite3_io_error_pending;
      int ioerr_cnt = sqlite3_io_error_pending;
      sqlite3_io_error_pending = -1;
#endif
      sqlite3pager_rollback(pPager);
#if defined(SQLITE_TEST) && (defined(OS_UNIX) || defined(OS_WIN))
      sqlite3_io_error_pending = ioerr_cnt;
#endif
      if( !MEMDB ){
        sqlite3OsUnlock(&pPager->fd, NO_LOCK);
      }
      assert( pPager->journalOpen==0 );
      break;
    }
    case PAGER_SHARED: {

**
*************************************************************************
** This file contains SQLite's grammar for SQL.  Process this file
** using the lemon parser generator to generate C code that runs
** the parser.  Lemon will also generate a header file containing
** numeric codes for all of the tokens.
**
** @(#) $Id: parse.y,v 1.162 2005/01/21 03:12:15 danielk1977 Exp $
*/
%token_prefix TK_
%token_type {Token}
%default_type {Token}
%extra_argument {Parse *pParse}
%syntax_error {
  if( pParse->zErrMsg==0 ){
................................................................................
  sqlite3DropTable(pParse, X, 1);
}
%endif // SQLITE_OMIT_VIEW

//////////////////////// The SELECT statement /////////////////////////////////
//
cmd ::= select(X).  {
  sqlite3Select(pParse, X, SRT_Callback, 0, 0, 0, 0, 0, 0);
  sqlite3SelectDelete(X);
}

%type select {Select*}
%destructor select {sqlite3SelectDelete($$);}
%type oneselect {Select*}
%destructor oneselect {sqlite3SelectDelete($$);}
................................................................................
%endif 
expr(A) ::= REGISTER(X).     {A = sqlite3RegisterExpr(pParse, &X);}
expr(A) ::= VARIABLE(X).     {
  Token *pToken = &X;
  Expr *pExpr = A = sqlite3Expr(TK_VARIABLE, 0, 0, pToken);
  sqlite3ExprAssignVarNumber(pParse, pExpr);
}
term(A) ::= ID(X) LP exprlist(Y) RP(E). {
  A = sqlite3ExprFunction(Y, &X);
  sqlite3ExprSpan(A,&X,&E);
}
expr(A) ::= ID(X) LP STAR RP(E). {
  A = sqlite3ExprFunction(0, &X);
  sqlite3ExprSpan(A,&X,&E);
}

**
*************************************************************************
** This file contains SQLite's grammar for SQL.  Process this file
** using the lemon parser generator to generate C code that runs
** the parser.  Lemon will also generate a header file containing
** numeric codes for all of the tokens.
**
** @(#) $Id: parse.y,v 1.163 2005/01/29 08:32:45 danielk1977 Exp $
*/
%token_prefix TK_
%token_type {Token}
%default_type {Token}
%extra_argument {Parse *pParse}
%syntax_error {
  if( pParse->zErrMsg==0 ){
................................................................................
  sqlite3DropTable(pParse, X, 1);
}
%endif // SQLITE_OMIT_VIEW

//////////////////////// The SELECT statement /////////////////////////////////
//
cmd ::= select(X).  {
  sqlite3Select(pParse, X, SRT_Callback, 0, 0, 0, 0, 0);
  sqlite3SelectDelete(X);
}

%type select {Select*}
%destructor select {sqlite3SelectDelete($$);}
%type oneselect {Select*}
%destructor oneselect {sqlite3SelectDelete($$);}
................................................................................
%endif 
expr(A) ::= REGISTER(X).     {A = sqlite3RegisterExpr(pParse, &X);}
expr(A) ::= VARIABLE(X).     {
  Token *pToken = &X;
  Expr *pExpr = A = sqlite3Expr(TK_VARIABLE, 0, 0, pToken);
  sqlite3ExprAssignVarNumber(pParse, pExpr);
}
expr(A) ::= ID(X) LP exprlist(Y) RP(E). {
  A = sqlite3ExprFunction(Y, &X);
  sqlite3ExprSpan(A,&X,&E);
}
expr(A) ::= ID(X) LP STAR RP(E). {
  A = sqlite3ExprFunction(0, &X);
  sqlite3ExprSpan(A,&X,&E);
}

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.234 2005/01/26 03:58:36 danielk1977 Exp $
*/
#include "sqliteInt.h"


/*
** Allocate a new Select structure and return a pointer to that
** structure.
................................................................................
  sqlite3SelectDelete(p->pPrior);
  sqliteFree(p);
}

/*
** Delete the aggregate information from the parse structure.
*/

static void sqliteAggregateInfoReset(Parse *pParse){
  sqliteFree(pParse->aAgg);
  pParse->aAgg = 0;
  pParse->nAgg = 0;
  pParse->useAgg = 0;
}


/*
** Insert code into "v" that will push the record on the top of the
** stack into the sorter.
*/
static void pushOntoSorter(Parse *pParse, Vdbe *v, ExprList *pOrderBy){
  int i;
................................................................................
**
** If the declaration type is the exact datatype definition extracted from
** the original CREATE TABLE statement if the expression is a column.
** 
** The declaration type for an expression is either TEXT, NUMERIC or ANY.
** The declaration type for a ROWID field is INTEGER.
*/
static const char *columnType(Parse *pParse, SrcList *pTabList, Expr *pExpr){
  char const *zType;
  int j;
  if( pExpr==0 || pTabList==0 ) return 0;

  sqlite3ExprResolveNames(pParse, pTabList, 0, 0, pExpr, 1, 0);

  /* The TK_AS operator can only occur in ORDER BY, GROUP BY, HAVING,
  ** and LIMIT clauses.  But pExpr originates in the result set of a
  ** SELECT.  So pExpr can never contain an AS operator.
  */
  assert( pExpr->op!=TK_AS );

  switch( pExpr->op ){
    case TK_COLUMN: {
      Table *pTab;
      int iCol = pExpr->iColumn;


      for(j=0; j<pTabList->nSrc && pTabList->a[j].iCursor!=pExpr->iTable; j++){}
      assert( j<pTabList->nSrc );
      pTab = pTabList->a[j].pTab;





      if( iCol<0 ) iCol = pTab->iPKey;
      assert( iCol==-1 || (iCol>=0 && iCol<pTab->nCol) );
      if( iCol<0 ){
        zType = "INTEGER";
      }else{
        zType = pTab->aCol[iCol].zType;
      }
      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case TK_SELECT: {

      Select *pS = pExpr->pSelect;


      zType = columnType(pParse, pS->pSrc, pS->pEList->a[0].pExpr); 
      break;
    }
#endif
    default:
      zType = 0;
  }
  
................................................................................
static void generateColumnTypes(
  Parse *pParse,      /* Parser context */
  SrcList *pTabList,  /* List of tables */
  ExprList *pEList    /* Expressions defining the result set */
){
  Vdbe *v = pParse->pVdbe;
  int i;


  for(i=0; i<pEList->nExpr; i++){
    Expr *p = pEList->a[i].pExpr;
    const char *zType = columnType(pParse, pTabList, p);
    if( zType==0 ) continue;
    /* The vdbe must make it's own copy of the column-type, in case the 
    ** schema is reset before this virtual machine is deleted.
    */
    sqlite3VdbeSetColName(v, i+pEList->nExpr, zType, strlen(zType));
  }
}
................................................................................
  pTab->aCol = aCol = sqliteMalloc( sizeof(pTab->aCol[0])*pTab->nCol );
  for(i=0, pCol=aCol; i<pTab->nCol; i++, pCol++){
    Expr *p, *pR;
    char *zType;
    char *zName;
    char *zBasename;
    int cnt;

    
    /* Get an appropriate name for the column
    */
    p = pEList->a[i].pExpr;
    assert( p->pRight==0 || p->pRight->token.z==0 || p->pRight->token.z[0]!=0 );
    if( (zName = pEList->a[i].zName)!=0 ){
      /* If the column contains an "AS <name>" phrase, use <name> as the name */
................................................................................
      sqliteFree(zBasename);
    }
    pCol->zName = zName;

    /* Get the typename, type affinity, and collating sequence for the
    ** column.
    */

    zType = sqliteStrDup(columnType(pParse, pSelect->pSrc ,p));
    pCol->zType = zType;
    pCol->affinity = SQLITE_AFF_NUMERIC;
    if( zType ){
      pCol->affinity = sqlite3AffinityType(zType, strlen(zType));
    }
    pCol->pColl = sqlite3ExprCollSeq(pParse, p);
    if( !pCol->pColl ){
................................................................................
#ifndef SQLITE_OMIT_SUBQUERY
      /* A sub-query in the FROM clause of a SELECT */
      assert( pFrom->pSelect!=0 );
      if( pFrom->zAlias==0 ){
        pFrom->zAlias =
          sqlite3MPrintf("sqlite_subquery_%p_", (void*)pFrom->pSelect);
      }

      pFrom->pTab = pTab = 
        sqlite3ResultSetOfSelect(pParse, pFrom->zAlias, pFrom->pSelect);
      if( pTab==0 ){
        return 1;
      }
      /* The isTransient flag indicates that the Table structure has been
      ** dynamically allocated and may be freed at any time.  In other words,
................................................................................
  /* Generate code for the left and right SELECT statements.
  */
  switch( p->op ){
    case TK_ALL: {
      if( p->pOrderBy==0 ){
        pPrior->nLimit = p->nLimit;
        pPrior->nOffset = p->nOffset;
        rc = sqlite3Select(pParse, pPrior, eDest, iParm, 0, 0, 0, aff, 0);
        if( rc ){
          goto multi_select_end;
        }
        p->pPrior = 0;
        p->iLimit = pPrior->iLimit;
        p->iOffset = pPrior->iOffset;
        p->nLimit = -1;
        p->nOffset = 0;
        rc = sqlite3Select(pParse, p, eDest, iParm, 0, 0, 0, aff, 0);
        p->pPrior = pPrior;
        if( rc ){
          goto multi_select_end;
        }
        break;
      }
      /* For UNION ALL ... ORDER BY fall through to the next case */
................................................................................
	assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
        aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, unionTab, 0);
        assert( p->pEList );
      }

      /* Code the SELECT statements to our left
      */

      rc = sqlite3Select(pParse, pPrior, priorOp, unionTab, 0, 0, 0, aff, 0);
      if( rc ){
        goto multi_select_end;
      }

      /* Code the current SELECT statement
      */
      switch( p->op ){
................................................................................
      p->pPrior = 0;
      pOrderBy = p->pOrderBy;
      p->pOrderBy = 0;
      nLimit = p->nLimit;
      p->nLimit = -1;
      nOffset = p->nOffset;
      p->nOffset = 0;
      rc = sqlite3Select(pParse, p, op, unionTab, 0, 0, 0, aff, 0);
      p->pPrior = pPrior;
      p->pOrderBy = pOrderBy;
      p->nLimit = nLimit;
      p->nOffset = nOffset;
      p->iLimit = -1;
      p->iOffset = -1;
      if( rc ){
................................................................................
      sqlite3VdbeAddOp(v, OP_KeyAsData, tab1, 1);
      assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
      aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, tab1, 0);
      assert( p->pEList );

      /* Code the SELECTs to our left into temporary table "tab1".
      */
      rc = sqlite3Select(pParse, pPrior, SRT_Union, tab1, 0, 0, 0, aff, 0);
      if( rc ){
        goto multi_select_end;
      }

      /* Code the current SELECT into temporary table "tab2"
      */
      addr = sqlite3VdbeAddOp(v, OP_OpenTemp, tab2, 0);
................................................................................
      assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
      aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, tab2, 0);
      p->pPrior = 0;
      nLimit = p->nLimit;
      p->nLimit = -1;
      nOffset = p->nOffset;
      p->nOffset = 0;
      rc = sqlite3Select(pParse, p, SRT_Union, tab2, 0, 0, 0, aff, 0);
      p->pPrior = pPrior;
      p->nLimit = nLimit;
      p->nOffset = nOffset;
      if( rc ){
        goto multi_select_end;
      }

................................................................................

    if( p->pOrderBy ){
      struct ExprList_item *pOrderByTerm = p->pOrderBy->a;
      for(i=0; i<p->pOrderBy->nExpr; i++, pOrderByTerm++){
        Expr *pExpr = pOrderByTerm->pExpr;
        char *zName = pOrderByTerm->zName;
        assert( pExpr->op==TK_COLUMN && pExpr->iColumn<nCol );
        assert( !pExpr->pColl );
        if( zName ){
          pExpr->pColl = sqlite3LocateCollSeq(pParse, zName, -1);
        }else{
          pExpr->pColl = pKeyInfo->aColl[pExpr->iColumn];
        }
      }
      generateSortTail(pParse, p, v, p->pEList->nExpr, eDest, iParm);
................................................................................
** whose result set is defined by pEList appears as entry in the
** FROM clause of a SELECT such that the VDBE cursor assigned to that
** FORM clause entry is iTable.  This routine make the necessary 
** changes to pExpr so that it refers directly to the source table
** of the subquery rather the result set of the subquery.
*/
static void substExprList(ExprList*,int,ExprList*);  /* Forward Decl */

static void substExpr(Expr *pExpr, int iTable, ExprList *pEList){
  if( pExpr==0 ) return;
  if( pExpr->op==TK_COLUMN && pExpr->iTable==iTable ){
    if( pExpr->iColumn<0 ){
      pExpr->op = TK_NULL;
    }else{
      Expr *pNew;
................................................................................
      pExpr->iAgg = pNew->iAgg;
      sqlite3TokenCopy(&pExpr->token, &pNew->token);
      sqlite3TokenCopy(&pExpr->span, &pNew->span);
    }
  }else{
    substExpr(pExpr->pLeft, iTable, pEList);
    substExpr(pExpr->pRight, iTable, pEList);

    substExprList(pExpr->pList, iTable, pEList);
  }
}
static void 
substExprList(ExprList *pList, int iTable, ExprList *pEList){
  int i;
  if( pList==0 ) return;
  for(i=0; i<pList->nExpr; i++){
    substExpr(pList->a[i].pExpr, iTable, pEList);
  }








}
#endif /* !defined(SQLITE_OMIT_VIEW) */

#ifndef SQLITE_OMIT_VIEW
/*
** This routine attempts to flatten subqueries in order to speed
** execution.  It returns 1 if it makes changes and 0 if no flattening
................................................................................
** the number of errors seen.
**
** An ORDER BY or GROUP BY is a list of expressions.  If any expression
** is an integer constant, then that expression is replaced by the
** corresponding entry in the result set.
*/
static int processOrderGroupBy(
  Parse *pParse,        /* Parsing context */
  ExprList *pOrderBy,   /* The ORDER BY or GROUP BY clause to be processed */
  SrcList *pTabList,    /* The FROM clause */
  ExprList *pEList,     /* The result set */
  NameContext *pNC,     /* Name context for enclosing query */
  int isAgg,            /* True if aggregate functions are involved */
  const char *zType     /* Either "ORDER" or "GROUP", as appropriate */
){
  int i;




  if( pOrderBy==0 ) return 0;
  for(i=0; i<pOrderBy->nExpr; i++){
    int iCol;
    Expr *pE = pOrderBy->a[i].pExpr;
    if( sqlite3ExprIsInteger(pE, &iCol) && iCol>0 && iCol<=pEList->nExpr ){

      sqlite3ExprDelete(pE);
      pE = pOrderBy->a[i].pExpr = sqlite3ExprDup(pEList->a[iCol-1].pExpr);
    }
    if( sqlite3ExprResolveNames(pParse, pTabList, pEList, pNC, pE, isAgg, 1) ){
      return 1;
    }
    if( sqlite3ExprIsConstant(pE) ){
      if( sqlite3ExprIsInteger(pE, &iCol)==0 ){
        sqlite3ErrorMsg(pParse,
          "%s BY terms must not be non-integer constants", zType);
        return 1;
      }else if( iCol<=0 || iCol>pEList->nExpr ){
        sqlite3ErrorMsg(pParse, 
           "%s BY column number %d out of range - should be "
           "between 1 and %d", zType, iCol, pEList->nExpr);
        return 1;
      }
    }


  }






  return 0;
}















































































































































/*
** Generate code for the given SELECT statement.
**
** The results are distributed in various ways depending on the
** value of eDest and iParm.
**
**     eDest Value       Result
................................................................................
  Parse *pParse,         /* The parser context */
  Select *p,             /* The SELECT statement being coded. */
  int eDest,             /* How to dispose of the results */
  int iParm,             /* A parameter used by the eDest disposal method */
  Select *pParent,       /* Another SELECT for which this is a sub-query */
  int parentTab,         /* Index in pParent->pSrc of this query */
  int *pParentAgg,       /* True if pParent uses aggregate functions */
  char *aff,             /* If eDest is SRT_Union, the affinity string */
  NameContext *pNC       /* Namespace of the next outer query */
){
  int i;
  WhereInfo *pWInfo;
  Vdbe *v;
  int isAgg = 0;         /* True for select lists like "count(*)" */
  ExprList *pEList;      /* List of columns to extract. */
  SrcList *pTabList;     /* List of tables to select from */
  Expr *pWhere;          /* The WHERE clause.  May be NULL */
  ExprList *pOrderBy;    /* The ORDER BY clause.  May be NULL */
  ExprList *pGroupBy;    /* The GROUP BY clause.  May be NULL */
  Expr *pHaving;         /* The HAVING clause.  May be NULL */
  int isDistinct;        /* True if the DISTINCT keyword is present */
  int distinct;          /* Table to use for the distinct set */
  int rc = 1;            /* Value to return from this function */


  if( sqlite3_malloc_failed || pParse->nErr || p==0 ) return 1;
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;

#ifndef SQLITE_OMIT_COMPOUND_SELECT
  /* If there is are a sequence of queries, do the earlier ones first.
  */
................................................................................
      sqlite3ErrorMsg(pParse, "cursors cannot be used on compound queries");
      goto select_end;
    }
#endif
    return multiSelect(pParse, p, eDest, iParm, aff);
  }
#endif











  /* Make local copies of the parameters for this query.
  */
  pTabList = p->pSrc;
  pWhere = p->pWhere;
  pOrderBy = p->pOrderBy;
  pGroupBy = p->pGroupBy;
  pHaving = p->pHaving;

  isDistinct = p->isDistinct;



  /* 
  ** Do not even attempt to generate any code if we have already seen
  ** errors before this routine starts.
  */
  if( pParse->nErr>0 ) goto select_end;

  if( prepSelectStmt(pParse, p) ){
    goto select_end;
  }
  pWhere = p->pWhere;
  pEList = p->pEList;
  if( pEList==0 ) goto select_end;

  /* If writing to memory or generating a set
  ** only a single column may be output.
  */
  assert( eDest!=SRT_Exists || pEList->nExpr==1 );
#ifndef SQLITE_OMIT_SUBQUERY
  if( (eDest==SRT_Mem || eDest==SRT_Set) && pEList->nExpr>1 ){
    sqlite3ErrorMsg(pParse, "only a single result allowed for "
................................................................................
    case SRT_Discard:
      pOrderBy = 0;
      break;
    default:
      break;
  }

  /* At this point, we should have allocated all the cursors that we
  ** need to handle subquerys and temporary tables.  
  **
  ** Resolve the column names and do a semantics check on all the expressions.
  */
  for(i=0; i<pEList->nExpr; i++){
    Expr *pX = pEList->a[i].pExpr;
    if( sqlite3ExprResolveNames(pParse, pTabList, 0, pNC, pX, 1, 1) ){
      goto select_end;
    }
    if( ExprHasProperty(pX, EP_Agg) ) isAgg = 1;
  }
  if( sqlite3ExprResolveNames(pParse, pTabList, pEList, pNC, pWhere, 0, 1) ){
    goto select_end;
  }
  if( pHaving ){
    if( pGroupBy==0 ){
      sqlite3ErrorMsg(pParse, "a GROUP BY clause is required before HAVING");
      goto select_end;
    }
    if( sqlite3ExprResolveNames(pParse, pTabList, pEList, pNC, pHaving, 1, 1) ){
      goto select_end;
    }
  }
  if( pGroupBy ){
    isAgg = 1;
  }
  if( processOrderGroupBy(pParse,pOrderBy,pTabList,pEList,pNC,isAgg,"ORDER")
   || processOrderGroupBy(pParse,pGroupBy,pTabList,pEList,pNC,isAgg,"GROUP")
  ){
    goto select_end;
  }

  /* We cannot use a SQL cursor on a join or on a DISTINCT query
  */
#ifndef SQLITE_OMIT_CURSOR
  if( p->pFetch ){
    if( p->isDistinct ){
      sqlite3ErrorMsg(pParse, "cursors cannot be used on DISTINCT queries");
      goto select_end;
................................................................................
      zSavedAuthContext = pParse->zAuthContext;
      pParse->zAuthContext = pTabList->a[i].zName;
      needRestoreContext = 1;
    }else{
      needRestoreContext = 0;
    }
    sqlite3Select(pParse, pTabList->a[i].pSelect, SRT_TempTable, 
                 pTabList->a[i].iCursor, p, i, &isAgg, 0, 0);
    if( needRestoreContext ){
      pParse->zAuthContext = zSavedAuthContext;
    }
    pTabList = p->pSrc;
    pWhere = p->pWhere;
    if( eDest!=SRT_Union && eDest!=SRT_Except && eDest!=SRT_Discard ){
      pOrderBy = p->pOrderBy;
................................................................................
  /* Check to see if this is a subquery that can be "flattened" into its parent.
  ** If flattening is a possiblity, do so and return immediately.  
  */
#ifndef SQLITE_OMIT_VIEW
  if( pParent && pParentAgg &&
      flattenSubquery(pParse, pParent, parentTab, *pParentAgg, isAgg) ){
    if( isAgg ) *pParentAgg = 1;
    return rc;
  }
#endif

  /* If there is an ORDER BY clause, resolve any collation sequences
  ** names that have been explicitly specified.
  */
  if( pOrderBy ){
................................................................................
  if( eDest==SRT_TempTable ){
    sqlite3VdbeAddOp(v, OP_OpenTemp, iParm, 0);
    sqlite3VdbeAddOp(v, OP_SetNumColumns, iParm, pEList->nExpr);
  }

  /* Do an analysis of aggregate expressions.
  */
  sqliteAggregateInfoReset(pParse);
  if( isAgg || pGroupBy ){
    assert( pParse->nAgg==0 );
    isAgg = 1;
    for(i=0; i<pEList->nExpr; i++){
      if( sqlite3ExprAnalyzeAggregates(pParse, pEList->a[i].pExpr) ){
        goto select_end;
      }
................................................................................
  */
  rc = 0;

  /* Control jumps to here if an error is encountered above, or upon
  ** successful coding of the SELECT.
  */
select_end:
  sqliteAggregateInfoReset(pParse);
  return rc;
}

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.235 2005/01/29 08:32:45 danielk1977 Exp $
*/
#include "sqliteInt.h"


/*
** Allocate a new Select structure and return a pointer to that
** structure.
................................................................................
  sqlite3SelectDelete(p->pPrior);
  sqliteFree(p);
}

/*
** Delete the aggregate information from the parse structure.
*/
#if 0
static void sqliteAggregateInfoReset(Parse *pParse){
  sqliteFree(pParse->aAgg);
  pParse->aAgg = 0;
  pParse->nAgg = 0;
  pParse->useAgg = 0;
}
#endif

/*
** Insert code into "v" that will push the record on the top of the
** stack into the sorter.
*/
static void pushOntoSorter(Parse *pParse, Vdbe *v, ExprList *pOrderBy){
  int i;
................................................................................
**
** If the declaration type is the exact datatype definition extracted from
** the original CREATE TABLE statement if the expression is a column.
** 
** The declaration type for an expression is either TEXT, NUMERIC or ANY.
** The declaration type for a ROWID field is INTEGER.
*/
static const char *columnType(NameContext *pNC, Expr *pExpr){
  char const *zType;
  int j;
  if( pExpr==0 || pNC->pSrcList==0 ) return 0;



  /* The TK_AS operator can only occur in ORDER BY, GROUP BY, HAVING,
  ** and LIMIT clauses.  But pExpr originates in the result set of a
  ** SELECT.  So pExpr can never contain an AS operator.
  */
  assert( pExpr->op!=TK_AS );

  switch( pExpr->op ){
    case TK_COLUMN: {
      Table *pTab = 0;
      int iCol = pExpr->iColumn;
      while( pNC && !pTab ){
        SrcList *pTabList = pNC->pSrcList;
        for(j=0;j<pTabList->nSrc && pTabList->a[j].iCursor!=pExpr->iTable;j++);
        if( j<pTabList->nSrc ){
          pTab = pTabList->a[j].pTab;
        }else{
          pNC = pNC->pNext;
        }
      }
      assert( pTab );
      if( iCol<0 ) iCol = pTab->iPKey;
      assert( iCol==-1 || (iCol>=0 && iCol<pTab->nCol) );
      if( iCol<0 ){
        zType = "INTEGER";
      }else{
        zType = pTab->aCol[iCol].zType;
      }
      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case TK_SELECT: {
      NameContext sNC;
      Select *pS = pExpr->pSelect;
      sNC.pSrcList = pExpr->pSelect->pSrc;
      sNC.pNext = pNC;
      zType = columnType(&sNC, pS->pEList->a[0].pExpr); 
      break;
    }
#endif
    default:
      zType = 0;
  }
  
................................................................................
static void generateColumnTypes(
  Parse *pParse,      /* Parser context */
  SrcList *pTabList,  /* List of tables */
  ExprList *pEList    /* Expressions defining the result set */
){
  Vdbe *v = pParse->pVdbe;
  int i;
  NameContext sNC;
  sNC.pSrcList = pTabList;
  for(i=0; i<pEList->nExpr; i++){
    Expr *p = pEList->a[i].pExpr;
    const char *zType = columnType(&sNC, p);
    if( zType==0 ) continue;
    /* The vdbe must make it's own copy of the column-type, in case the 
    ** schema is reset before this virtual machine is deleted.
    */
    sqlite3VdbeSetColName(v, i+pEList->nExpr, zType, strlen(zType));
  }
}
................................................................................
  pTab->aCol = aCol = sqliteMalloc( sizeof(pTab->aCol[0])*pTab->nCol );
  for(i=0, pCol=aCol; i<pTab->nCol; i++, pCol++){
    Expr *p, *pR;
    char *zType;
    char *zName;
    char *zBasename;
    int cnt;
    NameContext sNC;
    
    /* Get an appropriate name for the column
    */
    p = pEList->a[i].pExpr;
    assert( p->pRight==0 || p->pRight->token.z==0 || p->pRight->token.z[0]!=0 );
    if( (zName = pEList->a[i].zName)!=0 ){
      /* If the column contains an "AS <name>" phrase, use <name> as the name */
................................................................................
      sqliteFree(zBasename);
    }
    pCol->zName = zName;

    /* Get the typename, type affinity, and collating sequence for the
    ** column.
    */
    sNC.pSrcList = pSelect->pSrc;
    zType = sqliteStrDup(columnType(&sNC, p));
    pCol->zType = zType;
    pCol->affinity = SQLITE_AFF_NUMERIC;
    if( zType ){
      pCol->affinity = sqlite3AffinityType(zType, strlen(zType));
    }
    pCol->pColl = sqlite3ExprCollSeq(pParse, p);
    if( !pCol->pColl ){
................................................................................
#ifndef SQLITE_OMIT_SUBQUERY
      /* A sub-query in the FROM clause of a SELECT */
      assert( pFrom->pSelect!=0 );
      if( pFrom->zAlias==0 ){
        pFrom->zAlias =
          sqlite3MPrintf("sqlite_subquery_%p_", (void*)pFrom->pSelect);
      }
      sqlite3SelectResolve(pParse, pFrom->pSelect, 0);
      pFrom->pTab = pTab = 
        sqlite3ResultSetOfSelect(pParse, pFrom->zAlias, pFrom->pSelect);
      if( pTab==0 ){
        return 1;
      }
      /* The isTransient flag indicates that the Table structure has been
      ** dynamically allocated and may be freed at any time.  In other words,
................................................................................
  /* Generate code for the left and right SELECT statements.
  */
  switch( p->op ){
    case TK_ALL: {
      if( p->pOrderBy==0 ){
        pPrior->nLimit = p->nLimit;
        pPrior->nOffset = p->nOffset;
        rc = sqlite3Select(pParse, pPrior, eDest, iParm, 0, 0, 0, aff);
        if( rc ){
          goto multi_select_end;
        }
        p->pPrior = 0;
        p->iLimit = pPrior->iLimit;
        p->iOffset = pPrior->iOffset;
        p->nLimit = -1;
        p->nOffset = 0;
        rc = sqlite3Select(pParse, p, eDest, iParm, 0, 0, 0, aff);
        p->pPrior = pPrior;
        if( rc ){
          goto multi_select_end;
        }
        break;
      }
      /* For UNION ALL ... ORDER BY fall through to the next case */
................................................................................
	assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
        aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, unionTab, 0);
        assert( p->pEList );
      }

      /* Code the SELECT statements to our left
      */
      assert( !pPrior->pOrderBy );
      rc = sqlite3Select(pParse, pPrior, priorOp, unionTab, 0, 0, 0, aff);
      if( rc ){
        goto multi_select_end;
      }

      /* Code the current SELECT statement
      */
      switch( p->op ){
................................................................................
      p->pPrior = 0;
      pOrderBy = p->pOrderBy;
      p->pOrderBy = 0;
      nLimit = p->nLimit;
      p->nLimit = -1;
      nOffset = p->nOffset;
      p->nOffset = 0;
      rc = sqlite3Select(pParse, p, op, unionTab, 0, 0, 0, aff);
      p->pPrior = pPrior;
      p->pOrderBy = pOrderBy;
      p->nLimit = nLimit;
      p->nOffset = nOffset;
      p->iLimit = -1;
      p->iOffset = -1;
      if( rc ){
................................................................................
      sqlite3VdbeAddOp(v, OP_KeyAsData, tab1, 1);
      assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
      aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, tab1, 0);
      assert( p->pEList );

      /* Code the SELECTs to our left into temporary table "tab1".
      */
      rc = sqlite3Select(pParse, pPrior, SRT_Union, tab1, 0, 0, 0, aff);
      if( rc ){
        goto multi_select_end;
      }

      /* Code the current SELECT into temporary table "tab2"
      */
      addr = sqlite3VdbeAddOp(v, OP_OpenTemp, tab2, 0);
................................................................................
      assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
      aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, tab2, 0);
      p->pPrior = 0;
      nLimit = p->nLimit;
      p->nLimit = -1;
      nOffset = p->nOffset;
      p->nOffset = 0;
      rc = sqlite3Select(pParse, p, SRT_Union, tab2, 0, 0, 0, aff);
      p->pPrior = pPrior;
      p->nLimit = nLimit;
      p->nOffset = nOffset;
      if( rc ){
        goto multi_select_end;
      }

................................................................................

    if( p->pOrderBy ){
      struct ExprList_item *pOrderByTerm = p->pOrderBy->a;
      for(i=0; i<p->pOrderBy->nExpr; i++, pOrderByTerm++){
        Expr *pExpr = pOrderByTerm->pExpr;
        char *zName = pOrderByTerm->zName;
        assert( pExpr->op==TK_COLUMN && pExpr->iColumn<nCol );
        /* assert( !pExpr->pColl ); */
        if( zName ){
          pExpr->pColl = sqlite3LocateCollSeq(pParse, zName, -1);
        }else{
          pExpr->pColl = pKeyInfo->aColl[pExpr->iColumn];
        }
      }
      generateSortTail(pParse, p, v, p->pEList->nExpr, eDest, iParm);
................................................................................
** whose result set is defined by pEList appears as entry in the
** FROM clause of a SELECT such that the VDBE cursor assigned to that
** FORM clause entry is iTable.  This routine make the necessary 
** changes to pExpr so that it refers directly to the source table
** of the subquery rather the result set of the subquery.
*/
static void substExprList(ExprList*,int,ExprList*);  /* Forward Decl */
static void substSelect(Select *, int, ExprList *);  /* Forward Decl */
static void substExpr(Expr *pExpr, int iTable, ExprList *pEList){
  if( pExpr==0 ) return;
  if( pExpr->op==TK_COLUMN && pExpr->iTable==iTable ){
    if( pExpr->iColumn<0 ){
      pExpr->op = TK_NULL;
    }else{
      Expr *pNew;
................................................................................
      pExpr->iAgg = pNew->iAgg;
      sqlite3TokenCopy(&pExpr->token, &pNew->token);
      sqlite3TokenCopy(&pExpr->span, &pNew->span);
    }
  }else{
    substExpr(pExpr->pLeft, iTable, pEList);
    substExpr(pExpr->pRight, iTable, pEList);
    substSelect(pExpr->pSelect, iTable, pEList);
    substExprList(pExpr->pList, iTable, pEList);
  }
}

static void substExprList(ExprList *pList, int iTable, ExprList *pEList){
  int i;
  if( pList==0 ) return;
  for(i=0; i<pList->nExpr; i++){
    substExpr(pList->a[i].pExpr, iTable, pEList);
  }
}
static void substSelect(Select *p, int iTable, ExprList *pEList){
  if( !p ) return;
  substExprList(p->pEList, iTable, pEList);
  substExprList(p->pGroupBy, iTable, pEList);
  substExprList(p->pOrderBy, iTable, pEList);
  substExpr(p->pHaving, iTable, pEList);
  substExpr(p->pWhere, iTable, pEList);
}
#endif /* !defined(SQLITE_OMIT_VIEW) */

#ifndef SQLITE_OMIT_VIEW
/*
** This routine attempts to flatten subqueries in order to speed
** execution.  It returns 1 if it makes changes and 0 if no flattening
................................................................................
** the number of errors seen.
**
** An ORDER BY or GROUP BY is a list of expressions.  If any expression
** is an integer constant, then that expression is replaced by the
** corresponding entry in the result set.
*/
static int processOrderGroupBy(
  NameContext *pNC,     /* Name context of the SELECT statement. */
  ExprList *pOrderBy,   /* The ORDER BY or GROUP BY clause to be processed */




  const char *zType     /* Either "ORDER" or "GROUP", as appropriate */
){
  int i;
  ExprList *pEList = pNC->pEList;     /* The result set of the SELECT */
  Parse *pParse = pNC->pParse;     /* The result set of the SELECT */
  assert( pEList );

  if( pOrderBy==0 ) return 0;
  for(i=0; i<pOrderBy->nExpr; i++){
    int iCol;
    Expr *pE = pOrderBy->a[i].pExpr;
    if( sqlite3ExprIsInteger(pE, &iCol) ){
      if( iCol>0 && iCol<=pEList->nExpr ){
        sqlite3ExprDelete(pE);
        pE = pOrderBy->a[i].pExpr = sqlite3ExprDup(pEList->a[iCol-1].pExpr);

      }else{








        sqlite3ErrorMsg(pParse, 
           "%s BY column number %d out of range - should be "
           "between 1 and %d", zType, iCol, pEList->nExpr);
        return 1;
      }
    }
    if( sqlite3ExprResolveNames(pNC, pE) ){
      return 1;
    }
    if( sqlite3ExprIsConstant(pE) ){
      sqlite3ErrorMsg(pParse,
          "%s BY terms must not be non-integer constants", zType);
      return 1;
    }
  }
  return 0;
}

/*
** This routine resolves any names used in the result set of the
** supplied SELECT statement. If the SELECT statement being resolved
** is a sub-select, then pOuterNC is a pointer to the NameContext 
** of the parent SELECT.
*/
int sqlite3SelectResolve(
  Parse *pParse,         /* The parser context */
  Select *p,             /* The SELECT statement being coded. */
  NameContext *pOuterNC  /* The outer name context. May be NULL. */
){
  ExprList *pEList;          /* Result set. */
  int i;                     /* For-loop variable used in multiple places */
  NameContext sNC;           /* Local name-context */

  /* If this routine has run before, return immediately. */
  if( p->isResolved ){
    assert( !pOuterNC );
    return SQLITE_OK;
  }
  p->isResolved = 1;

  /* If there have already been errors, do nothing. */
  if( pParse->nErr>0 ){
    return SQLITE_ERROR;
  }

  /* Prepare the select statement. This call will allocate all cursors
  ** required to handle the tables and subqueries in the FROM clause.
  */
  if( prepSelectStmt(pParse, p) ){
    return SQLITE_ERROR;
  }

  /* Set up the local name-context to pass to ExprResolveNames().  */
  sNC.pNext = pOuterNC;
  sNC.pParse = pParse;
  sNC.pSrcList = p->pSrc;
  sNC.allowAgg = 1;
  sNC.hasAgg = 0;
  sNC.nErr = 0;
  sNC.nRef = 0;
  sNC.pEList = 0;

  /* NameContext.nDepth stores the depth of recursion for this query. For
  ** an outer query (e.g. SELECT * FROM sqlite_master) this is 1. For
  ** a subquery it is 2. For a subquery of a subquery, 3. And so on. 
  ** Parse.nMaxDepth is the maximum depth for any subquery resolved so
  ** far. This is used to determine the number of aggregate contexts
  ** required at runtime.
  */
  sNC.nDepth = (pOuterNC?pOuterNC->nDepth+1:1);
  if( sNC.nDepth>pParse->nMaxDepth ){
    pParse->nMaxDepth = sNC.nDepth;
  }

  /* Resolve names in the result set. */
  pEList = p->pEList;
  if( !pEList ) return SQLITE_ERROR;
  for(i=0; i<pEList->nExpr; i++){
    Expr *pX = pEList->a[i].pExpr;
    if( sqlite3ExprResolveNames(&sNC, pX) ){
      return SQLITE_ERROR;
    }
  }

  /* If there are no aggregate functions in the result-set, and no GROUP BY 
  ** expression, do not allow aggregates in any of the other expressions.
  */
  assert( !p->isAgg );
  if( p->pGroupBy || sNC.hasAgg ){
    p->isAgg = 1;
  }else{
    sNC.allowAgg = 0;
  }

  /* If a HAVING clause is present, then there must be a GROUP BY clause.
  */
  if( p->pHaving && !p->pGroupBy ){
    sqlite3ErrorMsg(pParse, "a GROUP BY clause is required before HAVING");
    return SQLITE_ERROR;
  }

  /* Add the expression list to the name-context before parsing the
  ** other expressions in the SELECT statement. This is so that
  ** expressions in the WHERE clause (etc.) can refer to expressions by
  ** aliases in the result set.
  **
  ** Minor point: If this is the case, then the expression will be
  ** re-evaluated for each reference to it.
  */
  sNC.pEList = p->pEList;
  if( sqlite3ExprResolveNames(&sNC, p->pWhere) ||
      sqlite3ExprResolveNames(&sNC, p->pHaving) ||
      processOrderGroupBy(&sNC, p->pOrderBy, "ORDER") ||
      processOrderGroupBy(&sNC, p->pGroupBy, "GROUP")
  ){
    return SQLITE_ERROR;
  }

  return SQLITE_OK;
}

/*
** An instance of the following struct is used by sqlite3Select()
** to save aggregate related information from the Parse object
** at the start of each call and to restore it at the end. See
** saveAggregateInfo() and restoreAggregateInfo().
*/ 
struct AggregateInfo {
  u8 useAgg;
  int nAgg;
  AggExpr *aAgg;
};
typedef struct AggregateInfo AggregateInfo;

/* 
** Copy aggregate related information from the Parse structure
** into the AggregateInfo structure. Zero the aggregate related
** values in the Parse struct.
*/
static void saveAggregateInfo(Parse *pParse, AggregateInfo *pInfo){
  pInfo->aAgg = pParse->aAgg;
  pInfo->nAgg = pParse->nAgg;
  pInfo->useAgg = pParse->useAgg;
  pParse->aAgg = 0;
  pParse->nAgg = 0;
  pParse->useAgg = 0;
}

/*
** Copy aggregate related information from the AggregateInfo struct
** back into the Parse structure. The aggregate related information
** currently stored in the Parse structure is deleted.
*/
static void restoreAggregateInfo(Parse *pParse, AggregateInfo *pInfo){
  sqliteFree(pParse->aAgg);
  pParse->aAgg = pInfo->aAgg;
  pParse->nAgg = pInfo->nAgg;
  pParse->useAgg = pInfo->useAgg;
}
  
/*
** Generate code for the given SELECT statement.
**
** The results are distributed in various ways depending on the
** value of eDest and iParm.
**
**     eDest Value       Result
................................................................................
  Parse *pParse,         /* The parser context */
  Select *p,             /* The SELECT statement being coded. */
  int eDest,             /* How to dispose of the results */
  int iParm,             /* A parameter used by the eDest disposal method */
  Select *pParent,       /* Another SELECT for which this is a sub-query */
  int parentTab,         /* Index in pParent->pSrc of this query */
  int *pParentAgg,       /* True if pParent uses aggregate functions */
  char *aff              /* If eDest is SRT_Union, the affinity string */

){
  int i;
  WhereInfo *pWInfo;
  Vdbe *v;
  int isAgg;             /* True for select lists like "count(*)" */
  ExprList *pEList;      /* List of columns to extract. */
  SrcList *pTabList;     /* List of tables to select from */
  Expr *pWhere;          /* The WHERE clause.  May be NULL */
  ExprList *pOrderBy;    /* The ORDER BY clause.  May be NULL */
  ExprList *pGroupBy;    /* The GROUP BY clause.  May be NULL */
  Expr *pHaving;         /* The HAVING clause.  May be NULL */
  int isDistinct;        /* True if the DISTINCT keyword is present */
  int distinct;          /* Table to use for the distinct set */
  int rc = 1;            /* Value to return from this function */
  AggregateInfo sAggInfo;

  if( sqlite3_malloc_failed || pParse->nErr || p==0 ) return 1;
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;

#ifndef SQLITE_OMIT_COMPOUND_SELECT
  /* If there is are a sequence of queries, do the earlier ones first.
  */
................................................................................
      sqlite3ErrorMsg(pParse, "cursors cannot be used on compound queries");
      goto select_end;
    }
#endif
    return multiSelect(pParse, p, eDest, iParm, aff);
  }
#endif

  saveAggregateInfo(pParse, &sAggInfo);
  pOrderBy = p->pOrderBy;
  if( eDest==SRT_Union || eDest==SRT_Except || eDest==SRT_Discard ){
    p->pOrderBy = 0;
  }
  if( sqlite3SelectResolve(pParse, p, 0) ){
    goto select_end;
  }
  p->pOrderBy = pOrderBy;

  /* Make local copies of the parameters for this query.
  */
  pTabList = p->pSrc;
  pWhere = p->pWhere;

  pGroupBy = p->pGroupBy;
  pHaving = p->pHaving;
  isAgg = p->isAgg;
  isDistinct = p->isDistinct;
  pEList = p->pEList;
  if( pEList==0 ) goto select_end;

  /* 
  ** Do not even attempt to generate any code if we have already seen
  ** errors before this routine starts.
  */
  if( pParse->nErr>0 ) goto select_end;








  /* If writing to memory or generating a set
  ** only a single column may be output.
  */
  assert( eDest!=SRT_Exists || pEList->nExpr==1 );
#ifndef SQLITE_OMIT_SUBQUERY
  if( (eDest==SRT_Mem || eDest==SRT_Set) && pEList->nExpr>1 ){
    sqlite3ErrorMsg(pParse, "only a single result allowed for "
................................................................................
    case SRT_Discard:
      pOrderBy = 0;
      break;
    default:
      break;
  }


































  /* We cannot use a SQL cursor on a join or on a DISTINCT query
  */
#ifndef SQLITE_OMIT_CURSOR
  if( p->pFetch ){
    if( p->isDistinct ){
      sqlite3ErrorMsg(pParse, "cursors cannot be used on DISTINCT queries");
      goto select_end;
................................................................................
      zSavedAuthContext = pParse->zAuthContext;
      pParse->zAuthContext = pTabList->a[i].zName;
      needRestoreContext = 1;
    }else{
      needRestoreContext = 0;
    }
    sqlite3Select(pParse, pTabList->a[i].pSelect, SRT_TempTable, 
                 pTabList->a[i].iCursor, p, i, &isAgg, 0);
    if( needRestoreContext ){
      pParse->zAuthContext = zSavedAuthContext;
    }
    pTabList = p->pSrc;
    pWhere = p->pWhere;
    if( eDest!=SRT_Union && eDest!=SRT_Except && eDest!=SRT_Discard ){
      pOrderBy = p->pOrderBy;
................................................................................
  /* Check to see if this is a subquery that can be "flattened" into its parent.
  ** If flattening is a possiblity, do so and return immediately.  
  */
#ifndef SQLITE_OMIT_VIEW
  if( pParent && pParentAgg &&
      flattenSubquery(pParse, pParent, parentTab, *pParentAgg, isAgg) ){
    if( isAgg ) *pParentAgg = 1;
    goto select_end;
  }
#endif

  /* If there is an ORDER BY clause, resolve any collation sequences
  ** names that have been explicitly specified.
  */
  if( pOrderBy ){
................................................................................
  if( eDest==SRT_TempTable ){
    sqlite3VdbeAddOp(v, OP_OpenTemp, iParm, 0);
    sqlite3VdbeAddOp(v, OP_SetNumColumns, iParm, pEList->nExpr);
  }

  /* Do an analysis of aggregate expressions.
  */

  if( isAgg || pGroupBy ){
    assert( pParse->nAgg==0 );
    isAgg = 1;
    for(i=0; i<pEList->nExpr; i++){
      if( sqlite3ExprAnalyzeAggregates(pParse, pEList->a[i].pExpr) ){
        goto select_end;
      }
................................................................................
  */
  rc = 0;

  /* Control jumps to here if an error is encountered above, or upon
  ** successful coding of the SELECT.
  */
select_end:
  restoreAggregateInfo(pParse, &sAggInfo);
  return rc;
}

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.363 2005/01/22 03:03:55 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Cursor support is turned off unless the SQLITE_ENABLE_CURSOR option
** is defined.
................................................................................
** The following are the meanings of bits in the Expr.flags field.
*/
#define EP_FromJoin     0x0001  /* Originated in ON or USING clause of a join */
#define EP_Agg          0x0002  /* Contains one or more aggregate functions */
#define EP_Resolved     0x0004  /* IDs have been resolved to COLUMNs */
#define EP_Error        0x0008  /* Expression contains one or more errors */
#define EP_Not          0x0010  /* Operator preceeded by NOT */


/*
** These macros can be used to test, set, or clear bits in the 
** Expr.flags field.
*/
#define ExprHasProperty(E,P)     (((E)->flags&(P))==(P))
#define ExprHasAnyProperty(E,P)  (((E)->flags&(P))!=0)
................................................................................
*/
struct Fetch {
  SqlCursor *pCursor;  /* Cursor used by the fetch */
  int isBackwards;     /* Cursor moves backwards if true, forward if false */
  int doRewind;        /* True to rewind cursor before starting */
};


































/*
** An instance of the following structure contains all information
** needed to generate code for a single SELECT statement.
**
** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
** If there is a LIMIT clause, the parser sets nLimit to the value of the
** limit and nOffset to the value of the offset (or 0 if there is not
................................................................................
  Expr *pHaving;         /* The HAVING clause */
  ExprList *pOrderBy;    /* The ORDER BY clause */
  Select *pPrior;        /* Prior select in a compound select statement */
  int nLimit, nOffset;   /* LIMIT and OFFSET values.  -1 means not used */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
  IdList **ppOpenTemp;   /* OP_OpenTemp addresses used by multi-selects */
  Fetch *pFetch;         /* If this stmt is part of a FETCH command */


};

/*
** The results of a select can be distributed in several ways.
*/
#define SRT_Callback     1  /* Invoke a callback with each row of result */
#define SRT_Mem          2  /* Store result in a memory cell */
................................................................................
  int nTab;            /* Number of previously allocated VDBE cursors */
  int nMem;            /* Number of memory cells used so far */
  int nSet;            /* Number of sets used so far */
  u32 cookieMask;      /* Bitmask of schema verified databases */
  int cookieValue[MAX_ATTACHED+2];  /* Values of cookies to verify */
  int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
  u32 writeMask;       /* Start a write transaction on these databases */



  /* Above is constant between recursions.  Below is reset before and after
  ** each recursion */

  int nVar;            /* Number of '?' variables seen in the SQL so far */
  int nVarExpr;        /* Number of used slots in apVarExpr[] */
  int nVarExprAlloc;   /* Number of allocated slots in apVarExpr[] */
  Expr **apVarExpr;    /* Pointers to :aaa and $aaaa wildcard expressions */
  u8 explain;          /* True if the EXPLAIN flag is found on the query */
  u8 useAgg;           /* If true, extract field values from the aggregator
                       ** while generating expressions.  Normally false */
#ifndef SQLITE_OMIT_CURSOR
  u8 fetchDir;         /* The direction argument to the FETCH command */
  int dirArg1;         /* First argument to the direction */
  int dirArg2;         /* Second argument to the direction */
#endif
  int nAgg;            /* Number of aggregate expressions */
  AggExpr *aAgg;       /* An array of aggregate expressions */
  Token sErrToken;     /* The token at which the error occurred */
  Token sNameToken;    /* Token with unqualified schema object name */
  Token sLastToken;    /* The last token parsed */
  const char *zSql;    /* All SQL text */
  const char *zTail;   /* All SQL text past the last semicolon parsed */
  Table *pNewTable;    /* A table being constructed by CREATE TABLE */
  Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
  TriggerStack *trigStack;  /* Trigger actions being coded */
  const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */



};

/*
** An instance of the following structure can be declared on a stack and used
** to save the Parse.zAuthContext value so that it can be restored later.
*/
struct AuthContext {
................................................................................
** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
*/
typedef struct {
  sqlite3 *db;        /* The database being initialized */
  char **pzErrMsg;    /* Error message stored here */
} InitData;

/*
** A NameContext defines a context in which to resolve table and column
** names.  The context consists of a list of tables (the pSrcList) field and
** a list of named expression (pEList).  The named expression list may
** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
** to the table being operated on by INSERT, UPDATE, or DELETE.  The
** pEList corresponds to the result set of a SELECT and is NULL for
** other statements.
**
** NameContexts can be nested.  When resolving names, the inner-most 
** context is searched first.  If no match is found, the next outer
** context is checked.  If there is still no match, the next context
** is checked.  This process continues until either a match is found
** or all contexts are check.  When a match is found, the nRef member of
** the context containing the match is incremented. 
**
** Each subquery gets a new NameContext.  The pNext field points to the
** NameContext in the parent query.  Thus the process of scanning the
** NameContext list corresponds to searching through successively outer
** subqueries looking for a match.
*/
struct NameContext {
  Parse *pParse;       /* The parser */
  SrcList *pSrcList;   /* One or more tables used to resolve names */
  ExprList *pEList;    /* Optional list of named expressions */
  int nRef;            /* Number of names resolved by this context */
  int nErr;            /* Number of errors encountered while resolving names */
  u8 allowAgg;         /* Aggregate functions allowed here */
  u8 hasAgg;           /* Expression actually contains aggregate functions */
  NameContext *pNext;  /* Next outer name context.  NULL for outermost */
};

/*
** Each SQL cursor (a cursor created by the DECLARE ... CURSOR syntax)
** is represented by an instance of the following structure.
*/
struct SqlCursor {
  char *zName;           /* Name of this cursor */
  int idx;               /* Index of this cursor in db->apSqlCursor[] */
................................................................................
void sqlite3IdListDelete(IdList*);
void sqlite3SrcListDelete(SrcList*);
void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
                        Token*);
void sqlite3DropIndex(Parse*, SrcList*);
void sqlite3AddKeyType(Vdbe*, ExprList*);
void sqlite3AddIdxKeyType(Vdbe*, Index*);
int sqlite3Select(Parse*, Select*, int, int, Select*, int, int*,
                  char *aff, NameContext*);
Select *sqlite3SelectNew(ExprList*,SrcList*,Expr*,ExprList*,Expr*,ExprList*,
                        int,int,int);
void sqlite3SelectDelete(Select*);
void sqlite3SelectUnbind(Select*);
Table *sqlite3SrcListLookup(Parse*, SrcList*);
int sqlite3IsReadOnly(Parse*, Table*, int);
void sqlite3OpenTableForReading(Vdbe*, int iCur, Table*);
................................................................................
void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
void sqlite3Vacuum(Parse*, Token*);
int sqlite3RunVacuum(char**, sqlite3*);
char *sqlite3NameFromToken(Token*);
int sqlite3ExprCheck(Parse*, Expr*, int, int*);
int sqlite3ExprCompare(Expr*, Expr*);
int sqliteFuncId(Token*);
int sqlite3ExprResolveNames(Parse*, SrcList*, ExprList*, NameContext*,
                            Expr*, int, int);
int sqlite3ExprAnalyzeAggregates(Parse*, Expr*);
Vdbe *sqlite3GetVdbe(Parse*);
void sqlite3Randomness(int, void*);
void sqlite3RollbackAll(sqlite3*);
void sqlite3CodeVerifySchema(Parse*, int);
void sqlite3BeginTransaction(Parse*, int);
void sqlite3CommitTransaction(Parse*);
................................................................................
extern const unsigned char sqlite3UpperToLower[];
void sqlite3RootPageMoved(Db*, int, int);
void sqlite3Reindex(Parse*, Token*, Token*);
void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
int sqlite3GetToken(const unsigned char *, int *);
void sqlite3NestedParse(Parse*, const char*, ...);
void sqlite3ExpirePreparedStatements(sqlite3*);



#ifndef SQLITE_OMIT_CURSOR
void sqlite3CursorDelete(SqlCursor*);
void sqlite3CursorCreate(Parse*, Token*, Select*);
void sqlite3CursorClose(Parse*, Token*);
void sqlite3Fetch(Parse*, Token*, IdList*);
#endif /* SQLITE_OMIT_CURSOR */

#endif

**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.364 2005/01/29 08:32:45 danielk1977 Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Cursor support is turned off unless the SQLITE_ENABLE_CURSOR option
** is defined.
................................................................................
** The following are the meanings of bits in the Expr.flags field.
*/
#define EP_FromJoin     0x0001  /* Originated in ON or USING clause of a join */
#define EP_Agg          0x0002  /* Contains one or more aggregate functions */
#define EP_Resolved     0x0004  /* IDs have been resolved to COLUMNs */
#define EP_Error        0x0008  /* Expression contains one or more errors */
#define EP_Not          0x0010  /* Operator preceeded by NOT */
#define EP_VarSelect    0x0020  /* pSelect is correlated, not constant */

/*
** These macros can be used to test, set, or clear bits in the 
** Expr.flags field.
*/
#define ExprHasProperty(E,P)     (((E)->flags&(P))==(P))
#define ExprHasAnyProperty(E,P)  (((E)->flags&(P))!=0)
................................................................................
*/
struct Fetch {
  SqlCursor *pCursor;  /* Cursor used by the fetch */
  int isBackwards;     /* Cursor moves backwards if true, forward if false */
  int doRewind;        /* True to rewind cursor before starting */
};

/*
** A NameContext defines a context in which to resolve table and column
** names.  The context consists of a list of tables (the pSrcList) field and
** a list of named expression (pEList).  The named expression list may
** be NULL.  The pSrc corresponds to the FROM clause of a SELECT or
** to the table being operated on by INSERT, UPDATE, or DELETE.  The
** pEList corresponds to the result set of a SELECT and is NULL for
** other statements.
**
** NameContexts can be nested.  When resolving names, the inner-most 
** context is searched first.  If no match is found, the next outer
** context is checked.  If there is still no match, the next context
** is checked.  This process continues until either a match is found
** or all contexts are check.  When a match is found, the nRef member of
** the context containing the match is incremented. 
**
** Each subquery gets a new NameContext.  The pNext field points to the
** NameContext in the parent query.  Thus the process of scanning the
** NameContext list corresponds to searching through successively outer
** subqueries looking for a match.
*/
struct NameContext {
  Parse *pParse;       /* The parser */
  SrcList *pSrcList;   /* One or more tables used to resolve names */
  ExprList *pEList;    /* Optional list of named expressions */
  int nRef;            /* Number of names resolved by this context */
  int nErr;            /* Number of errors encountered while resolving names */
  u8 allowAgg;         /* Aggregate functions allowed here */
  u8 hasAgg;
  int nDepth;          /* Depth of subquery recursion. 1 for no recursion */
  NameContext *pNext;  /* Next outer name context.  NULL for outermost */
};

/*
** An instance of the following structure contains all information
** needed to generate code for a single SELECT statement.
**
** nLimit is set to -1 if there is no LIMIT clause.  nOffset is set to 0.
** If there is a LIMIT clause, the parser sets nLimit to the value of the
** limit and nOffset to the value of the offset (or 0 if there is not
................................................................................
  Expr *pHaving;         /* The HAVING clause */
  ExprList *pOrderBy;    /* The ORDER BY clause */
  Select *pPrior;        /* Prior select in a compound select statement */
  int nLimit, nOffset;   /* LIMIT and OFFSET values.  -1 means not used */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
  IdList **ppOpenTemp;   /* OP_OpenTemp addresses used by multi-selects */
  Fetch *pFetch;         /* If this stmt is part of a FETCH command */
  u8 isResolved;         /* True once sqlite3SelectResolve() has run. */
  u8 isAgg;              /* True if this is an aggregate query */
};

/*
** The results of a select can be distributed in several ways.
*/
#define SRT_Callback     1  /* Invoke a callback with each row of result */
#define SRT_Mem          2  /* Store result in a memory cell */
................................................................................
  int nTab;            /* Number of previously allocated VDBE cursors */
  int nMem;            /* Number of memory cells used so far */
  int nSet;            /* Number of sets used so far */
  u32 cookieMask;      /* Bitmask of schema verified databases */
  int cookieValue[MAX_ATTACHED+2];  /* Values of cookies to verify */
  int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
  u32 writeMask;       /* Start a write transaction on these databases */
  u8 useAgg;           /* If true, extract field values from the aggregator
                       ** while generating expressions.  Normally false */

  /* Above is constant between recursions.  Below is reset before and after
  ** each recursion */

  int nVar;            /* Number of '?' variables seen in the SQL so far */
  int nVarExpr;        /* Number of used slots in apVarExpr[] */
  int nVarExprAlloc;   /* Number of allocated slots in apVarExpr[] */
  Expr **apVarExpr;    /* Pointers to :aaa and $aaaa wildcard expressions */
  u8 explain;          /* True if the EXPLAIN flag is found on the query */


#ifndef SQLITE_OMIT_CURSOR
  u8 fetchDir;         /* The direction argument to the FETCH command */
  int dirArg1;         /* First argument to the direction */
  int dirArg2;         /* Second argument to the direction */
#endif


  Token sErrToken;     /* The token at which the error occurred */
  Token sNameToken;    /* Token with unqualified schema object name */
  Token sLastToken;    /* The last token parsed */
  const char *zSql;    /* All SQL text */
  const char *zTail;   /* All SQL text past the last semicolon parsed */
  Table *pNewTable;    /* A table being constructed by CREATE TABLE */
  Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
  TriggerStack *trigStack;  /* Trigger actions being coded */
  const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
  int nAgg;            /* Number of aggregate expressions */
  AggExpr *aAgg;       /* An array of aggregate expressions */
  int nMaxDepth;       /* Maximum depth of subquery recursion */
};

/*
** An instance of the following structure can be declared on a stack and used
** to save the Parse.zAuthContext value so that it can be restored later.
*/
struct AuthContext {
................................................................................
** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
*/
typedef struct {
  sqlite3 *db;        /* The database being initialized */
  char **pzErrMsg;    /* Error message stored here */
} InitData;

































/*
** Each SQL cursor (a cursor created by the DECLARE ... CURSOR syntax)
** is represented by an instance of the following structure.
*/
struct SqlCursor {
  char *zName;           /* Name of this cursor */
  int idx;               /* Index of this cursor in db->apSqlCursor[] */
................................................................................
void sqlite3IdListDelete(IdList*);
void sqlite3SrcListDelete(SrcList*);
void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
                        Token*);
void sqlite3DropIndex(Parse*, SrcList*);
void sqlite3AddKeyType(Vdbe*, ExprList*);
void sqlite3AddIdxKeyType(Vdbe*, Index*);
int sqlite3Select(Parse*, Select*, int, int, Select*, int, int*, char *aff);

Select *sqlite3SelectNew(ExprList*,SrcList*,Expr*,ExprList*,Expr*,ExprList*,
                        int,int,int);
void sqlite3SelectDelete(Select*);
void sqlite3SelectUnbind(Select*);
Table *sqlite3SrcListLookup(Parse*, SrcList*);
int sqlite3IsReadOnly(Parse*, Table*, int);
void sqlite3OpenTableForReading(Vdbe*, int iCur, Table*);
................................................................................
void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
void sqlite3Vacuum(Parse*, Token*);
int sqlite3RunVacuum(char**, sqlite3*);
char *sqlite3NameFromToken(Token*);
int sqlite3ExprCheck(Parse*, Expr*, int, int*);
int sqlite3ExprCompare(Expr*, Expr*);
int sqliteFuncId(Token*);
int sqlite3ExprResolveNames(NameContext *, Expr *);

int sqlite3ExprAnalyzeAggregates(Parse*, Expr*);
Vdbe *sqlite3GetVdbe(Parse*);
void sqlite3Randomness(int, void*);
void sqlite3RollbackAll(sqlite3*);
void sqlite3CodeVerifySchema(Parse*, int);
void sqlite3BeginTransaction(Parse*, int);
void sqlite3CommitTransaction(Parse*);
................................................................................
extern const unsigned char sqlite3UpperToLower[];
void sqlite3RootPageMoved(Db*, int, int);
void sqlite3Reindex(Parse*, Token*, Token*);
void sqlite3AlterRenameTable(Parse*, SrcList*, Token*);
int sqlite3GetToken(const unsigned char *, int *);
void sqlite3NestedParse(Parse*, const char*, ...);
void sqlite3ExpirePreparedStatements(sqlite3*);
void sqlite3CodeSubselect(Parse *, Expr *);
int sqlite3SelectResolve(Parse *, Select *, NameContext *);

#ifndef SQLITE_OMIT_CURSOR
void sqlite3CursorDelete(SqlCursor*);
void sqlite3CursorCreate(Parse*, Token*, Select*);
void sqlite3CursorClose(Parse*, Token*);
void sqlite3Fetch(Parse*, Token*, IdList*);
#endif /* SQLITE_OMIT_CURSOR */

#endif

    orconf = (orconfin == OE_Default)?pTriggerStep->orconf:orconfin;
    pParse->trigStack->orconf = orconf;
    switch( pTriggerStep->op ){
      case TK_SELECT: {
	Select * ss = sqlite3SelectDup(pTriggerStep->pSelect);		  
	assert(ss);
	assert(ss->pSrc);

	sqlite3Select(pParse, ss, SRT_Discard, 0, 0, 0, 0, 0, 0);
	sqlite3SelectDelete(ss);
	break;
      }
      case TK_UPDATE: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);
................................................................................
          !checkColumnOverLap(pTrigger->pColumns, pChanges) ){
        fire_this = 0;
      }
    }
 
    if( fire_this ){
      int endTrigger;
      SrcList dummyTablist;
      Expr * whenExpr;
      AuthContext sContext;


      dummyTablist.nSrc = 0;


      /* Push an entry on to the trigger stack */
      trigStackEntry.pTrigger = pTrigger;
      trigStackEntry.newIdx = newIdx;
      trigStackEntry.oldIdx = oldIdx;
      trigStackEntry.pTab = pTab;
      trigStackEntry.pNext = pParse->trigStack;
................................................................................
      trigStackEntry.ignoreJump = ignoreJump;
      pParse->trigStack = &trigStackEntry;
      sqlite3AuthContextPush(pParse, &sContext, pTrigger->name);

      /* code the WHEN clause */
      endTrigger = sqlite3VdbeMakeLabel(pParse->pVdbe);
      whenExpr = sqlite3ExprDup(pTrigger->pWhen);
      if( sqlite3ExprResolveNames(pParse, &dummyTablist, 0, 0, whenExpr, 0,1) ){
        pParse->trigStack = trigStackEntry.pNext;
        sqlite3ExprDelete(whenExpr);
        return 1;
      }
      sqlite3ExprIfFalse(pParse, whenExpr, endTrigger, 1);
      sqlite3ExprDelete(whenExpr);

    orconf = (orconfin == OE_Default)?pTriggerStep->orconf:orconfin;
    pParse->trigStack->orconf = orconf;
    switch( pTriggerStep->op ){
      case TK_SELECT: {
	Select * ss = sqlite3SelectDup(pTriggerStep->pSelect);		  
	assert(ss);
	assert(ss->pSrc);
        sqlite3SelectResolve(pParse, ss, 0);
	sqlite3Select(pParse, ss, SRT_Discard, 0, 0, 0, 0, 0);
	sqlite3SelectDelete(ss);
	break;
      }
      case TK_UPDATE: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);
................................................................................
          !checkColumnOverLap(pTrigger->pColumns, pChanges) ){
        fire_this = 0;
      }
    }
 
    if( fire_this ){
      int endTrigger;

      Expr * whenExpr;
      AuthContext sContext;
      NameContext sNC;

      memset(&sNC, 0, sizeof(sNC));
      sNC.pParse = pParse;

      /* Push an entry on to the trigger stack */
      trigStackEntry.pTrigger = pTrigger;
      trigStackEntry.newIdx = newIdx;
      trigStackEntry.oldIdx = oldIdx;
      trigStackEntry.pTab = pTab;
      trigStackEntry.pNext = pParse->trigStack;
................................................................................
      trigStackEntry.ignoreJump = ignoreJump;
      pParse->trigStack = &trigStackEntry;
      sqlite3AuthContextPush(pParse, &sContext, pTrigger->name);

      /* code the WHEN clause */
      endTrigger = sqlite3VdbeMakeLabel(pParse->pVdbe);
      whenExpr = sqlite3ExprDup(pTrigger->pWhen);
      if( sqlite3ExprResolveNames(&sNC, whenExpr) ){
        pParse->trigStack = trigStackEntry.pNext;
        sqlite3ExprDelete(whenExpr);
        return 1;
      }
      sqlite3ExprIfFalse(pParse, whenExpr, endTrigger, 1);
      sqlite3ExprDelete(whenExpr);

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle UPDATE statements.
**
** $Id: update.c,v 1.103 2005/01/19 23:24:51 drh Exp $
*/
#include "sqliteInt.h"

/*
** Process an UPDATE statement.
**
**   UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
................................................................................
  int *aXRef = 0;        /* aXRef[i] is the index in pChanges->a[] of the
                         ** an expression for the i-th column of the table.
                         ** aXRef[i]==-1 if the i-th column is not changed. */
  int chngRecno;         /* True if the record number is being changed */
  Expr *pRecnoExpr = 0;  /* Expression defining the new record number */
  int openAll = 0;       /* True if all indices need to be opened */
  AuthContext sContext;  /* The authorization context */


#ifndef SQLITE_OMIT_TRIGGER
  int isView;                  /* Trying to update a view */
  int triggers_exist = 0;      /* True if any row triggers exist */
#endif

  int newIdx      = -1;  /* index of trigger "new" temp table       */
................................................................................
  ** need to occur right after the database cursor.  So go ahead and
  ** allocate enough space, just in case.
  */
  pTabList->a[0].iCursor = iCur = pParse->nTab++;
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    pParse->nTab++;
  }






  /* Resolve the column names in all the expressions of the
  ** of the UPDATE statement.  Also find the column index
  ** for each column to be updated in the pChanges array.  For each
  ** column to be updated, make sure we have authorization to change
  ** that column.
  */
  chngRecno = 0;
  for(i=0; i<pChanges->nExpr; i++){
    if( sqlite3ExprResolveNames(pParse, pTabList, 0, 0,
          pChanges->a[i].pExpr, 0, 1) ){
      goto update_cleanup;
    }
    for(j=0; j<pTab->nCol; j++){
      if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
        if( j==pTab->iPKey ){
          chngRecno = 1;
          pRecnoExpr = pChanges->a[i].pExpr;
................................................................................
      aIdxUsed[j] = 0;
    }
  }

  /* Resolve the column names in all the expressions in the
  ** WHERE clause.
  */
  if( sqlite3ExprResolveNames(pParse, pTabList, 0, 0, pWhere, 0, 1) ){
    goto update_cleanup;
  }

  /* Start the view context
  */
  if( isView ){
    sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
................................................................................

  /* If we are trying to update a view, construct that view into
  ** a temporary table.
  */
  if( isView ){
    Select *pView;
    pView = sqlite3SelectDup(pTab->pSelect);
    sqlite3Select(pParse, pView, SRT_TempTable, iCur, 0, 0, 0, 0, 0);
    sqlite3SelectDelete(pView);
  }

  /* Begin the database scan
  */
  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0);
  if( pWInfo==0 ) goto update_cleanup;

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle UPDATE statements.
**
** $Id: update.c,v 1.104 2005/01/29 08:32:45 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** Process an UPDATE statement.
**
**   UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
................................................................................
  int *aXRef = 0;        /* aXRef[i] is the index in pChanges->a[] of the
                         ** an expression for the i-th column of the table.
                         ** aXRef[i]==-1 if the i-th column is not changed. */
  int chngRecno;         /* True if the record number is being changed */
  Expr *pRecnoExpr = 0;  /* Expression defining the new record number */
  int openAll = 0;       /* True if all indices need to be opened */
  AuthContext sContext;  /* The authorization context */
  NameContext sNC;       /* The name-context to resolve expressions in */

#ifndef SQLITE_OMIT_TRIGGER
  int isView;                  /* Trying to update a view */
  int triggers_exist = 0;      /* True if any row triggers exist */
#endif

  int newIdx      = -1;  /* index of trigger "new" temp table       */
................................................................................
  ** need to occur right after the database cursor.  So go ahead and
  ** allocate enough space, just in case.
  */
  pTabList->a[0].iCursor = iCur = pParse->nTab++;
  for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
    pParse->nTab++;
  }

  /* Initialize the name-context */
  memset(&sNC, 0, sizeof(sNC));
  sNC.pParse = pParse;
  sNC.pSrcList = pTabList;

  /* Resolve the column names in all the expressions of the
  ** of the UPDATE statement.  Also find the column index
  ** for each column to be updated in the pChanges array.  For each
  ** column to be updated, make sure we have authorization to change
  ** that column.
  */
  chngRecno = 0;
  for(i=0; i<pChanges->nExpr; i++){
    if( sqlite3ExprResolveNames(&sNC, pChanges->a[i].pExpr) ){

      goto update_cleanup;
    }
    for(j=0; j<pTab->nCol; j++){
      if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
        if( j==pTab->iPKey ){
          chngRecno = 1;
          pRecnoExpr = pChanges->a[i].pExpr;
................................................................................
      aIdxUsed[j] = 0;
    }
  }

  /* Resolve the column names in all the expressions in the
  ** WHERE clause.
  */
  if( sqlite3ExprResolveNames(&sNC, pWhere) ){
    goto update_cleanup;
  }

  /* Start the view context
  */
  if( isView ){
    sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
................................................................................

  /* If we are trying to update a view, construct that view into
  ** a temporary table.
  */
  if( isView ){
    Select *pView;
    pView = sqlite3SelectDup(pTab->pSelect);
    sqlite3Select(pParse, pView, SRT_TempTable, iCur, 0, 0, 0, 0);
    sqlite3SelectDelete(pView);
  }

  /* Begin the database scan
  */
  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0);
  if( pWInfo==0 ) goto update_cleanup;

**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.448 2005/01/27 00:33:21 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*
................................................................................
case OP_ListReset: {
  if( p->pList ){
    sqlite3VdbeKeylistFree(p->pList);
    p->pList = 0;
  }
  break;
}


























#ifndef SQLITE_OMIT_TRIGGER
/* Opcode: ContextPush * * * 
**
** Save the current Vdbe context such that it can be restored by a ContextPop
** opcode. The context stores the last insert row id, the last statement change
** count, and the current statement change count.
................................................................................
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: AggReset P1 P2 P3
**
** Reset the aggregator so that it no longer contains any data.
** Future aggregator elements will contain P2 values each and be sorted
** using the KeyInfo structure pointed to by P3.
**
** If P1 is non-zero, then only a single aggregator row is available (i.e.
** there is no GROUP BY expression). In this case it is illegal to invoke
** OP_AggFocus.
*/
case OP_AggReset: {
  assert( !pOp->p3 || pOp->p3type==P3_KEYINFO );
  if( pOp->p1 ){
    rc = sqlite3VdbeAggReset(0, &p->agg, (KeyInfo *)pOp->p3);
    p->agg.nMem = pOp->p2;    /* Agg.nMem is used by AggInsert() */
    rc = AggInsert(&p->agg, 0, 0);
  }else{
    rc = sqlite3VdbeAggReset(db, &p->agg, (KeyInfo *)pOp->p3);
    p->agg.nMem = pOp->p2;
  }
  if( rc!=SQLITE_OK ){
    goto abort_due_to_error;
  }
  p->agg.apFunc = sqliteMalloc( p->agg.nMem*sizeof(p->agg.apFunc[0]) );
  if( p->agg.apFunc==0 ) goto no_mem;
  break;
}

/* Opcode: AggInit * P2 P3
**
** Initialize the function parameters for an aggregate function.
** The aggregate will operate out of aggregate column P2.
** P3 is a pointer to the FuncDef structure for the function.
*/
case OP_AggInit: {
  int i = pOp->p2;
  assert( i>=0 && i<p->agg.nMem );
  p->agg.apFunc[i] = (FuncDef*)pOp->p3;
  break;
}

/* Opcode: AggFunc * P2 P3
**
** Execute the step function for an aggregate.  The
** function has P2 arguments.  P3 is a pointer to the FuncDef
................................................................................
  assert( apVal || n==0 );

  for(i=0; i<n; i++, pRec++){
    apVal[i] = pRec;
    storeTypeInfo(pRec, db->enc);
  }
  i = pTos->i;
  assert( i>=0 && i<p->agg.nMem );
  ctx.pFunc = (FuncDef*)pOp->p3;
  pMem = &p->agg.pCurrent->aMem[i];
  ctx.s.z = pMem->zShort;  /* Space used for small aggregate contexts */
  ctx.pAgg = pMem->z;
  ctx.cnt = ++pMem->i;
  ctx.isError = 0;
  ctx.pColl = 0;
  if( ctx.pFunc->needCollSeq ){
    assert( pOp>p->aOp );
................................................................................
  char *zKey;
  int nKey;
  int res;
  assert( pTos>=p->aStack );
  Stringify(pTos, db->enc);
  zKey = pTos->z;
  nKey = pTos->n;
  assert( p->agg.pBtree );
  assert( p->agg.pCsr );
  rc = sqlite3BtreeMoveto(p->agg.pCsr, zKey, nKey, &res);
  if( rc!=SQLITE_OK ){
    goto abort_due_to_error;
  }
  if( res==0 ){
    rc = sqlite3BtreeData(p->agg.pCsr, 0, sizeof(AggElem*),
        (char *)&p->agg.pCurrent);
    pc = pOp->p2 - 1;
  }else{
    rc = AggInsert(&p->agg, zKey, nKey);
  }
  if( rc!=SQLITE_OK ){
    goto abort_due_to_error;
  }
  Release(pTos);
  pTos--;
  break; 
................................................................................
**
** Move the top of the stack into the P2-th field of the current
** aggregate.  String values are duplicated into new memory.
*/
case OP_AggSet: {
  AggElem *pFocus;
  int i = pOp->p2;
  pFocus = p->agg.pCurrent;
  assert( pTos>=p->aStack );
  if( pFocus==0 ) goto no_mem;
  assert( i>=0 && i<p->agg.nMem );
  rc = sqlite3VdbeMemMove(&pFocus->aMem[i], pTos);
  pTos--;
  break;
}

/* Opcode: AggGet * P2 *
**
................................................................................
** Push a new entry onto the stack which is a copy of the P2-th field
** of the current aggregate.  Strings are not duplicated so
** string values will be ephemeral.
*/
case OP_AggGet: {
  AggElem *pFocus;
  int i = pOp->p2;
  pFocus = p->agg.pCurrent;
  if( pFocus==0 ){
    int res;
    if( sqlite3_malloc_failed ) goto no_mem;
    rc = sqlite3BtreeFirst(p->agg.pCsr, &res);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    if( res!=0 ){
      rc = AggInsert(&p->agg,"",1);
      pFocus = p->agg.pCurrent;
    }else{
      rc = sqlite3BtreeData(p->agg.pCsr, 0, 4, (char *)&pFocus);
    }
  }
  assert( i>=0 && i<p->agg.nMem );
  pTos++;
  sqlite3VdbeMemShallowCopy(pTos, &pFocus->aMem[i], MEM_Ephem);
  if( pTos->flags&MEM_Str ){
    sqlite3VdbeChangeEncoding(pTos, db->enc);
  }
  break;
}
................................................................................
** zero or more AggNext operations.  You must not execute an AggFocus
** in between an AggNext and an AggReset.
*/
case OP_AggNext: {
  int res;
  assert( rc==SQLITE_OK );
  CHECK_FOR_INTERRUPT;
  if( p->agg.searching==0 ){
    p->agg.searching = 1;
    if( p->agg.pCsr ){
      rc = sqlite3BtreeFirst(p->agg.pCsr, &res);
    }else{
      res = 0;
    }
  }else{
    if( p->agg.pCsr ){
      rc = sqlite3BtreeNext(p->agg.pCsr, &res);
    }else{
      res = 1;
    }
  }
  if( rc!=SQLITE_OK ) goto abort_due_to_error;
  if( res!=0 ){
    pc = pOp->p2 - 1;
  }else{
    int i;
    sqlite3_context ctx;
    Mem *aMem;

    if( p->agg.pCsr ){
      rc = sqlite3BtreeData(p->agg.pCsr, 0, sizeof(AggElem*),
          (char *)&p->agg.pCurrent);
      if( rc!=SQLITE_OK ) goto abort_due_to_error;
    }
    aMem = p->agg.pCurrent->aMem;
    for(i=0; i<p->agg.nMem; i++){
      FuncDef *pFunc = p->agg.apFunc[i];
      Mem *pMem = &aMem[i];
      if( pFunc==0 || pFunc->xFinalize==0 ) continue;
      ctx.s.flags = MEM_Null;
      ctx.s.z = pMem->zShort;
      ctx.pAgg = (void*)pMem->z;
      ctx.cnt = pMem->i;
      ctx.pFunc = pFunc;
................................................................................
  if( !pOp->p1 ){
    sqlite3ExpirePreparedStatements(db);
  }else{
    p->expired = 1;
  }
  break;
}



/* An other opcode is illegal...
*/
default: {
  sqlite3_snprintf(sizeof(zBuf),zBuf,"%d",pOp->opcode);
  sqlite3SetString(&p->zErrMsg, "unknown opcode ", zBuf, (char*)0);

**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.449 2005/01/29 08:32:45 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*
................................................................................
case OP_ListReset: {
  if( p->pList ){
    sqlite3VdbeKeylistFree(p->pList);
    p->pList = 0;
  }
  break;
}

#ifndef SQLITE_OMIT_SUBQUERY
/* Opcode: AggContextPush * * * 
**
** Save the state of the current aggregator. It is restored an 
** AggContextPop opcode.
** 
*/
case OP_AggContextPush: {
  p->pAgg++;
  assert( p->pAgg<&p->apAgg[p->nAgg] );
  break;
}

/* Opcode: AggContextPop * * *
**
** Restore the aggregator to the state it was in when AggContextPush
** was last called. Any data in the current aggregator is deleted.
*/
case OP_AggContextPop: {
  p->pAgg--;
  assert( p->pAgg>=p->apAgg );
  break;
}
#endif

#ifndef SQLITE_OMIT_TRIGGER
/* Opcode: ContextPush * * * 
**
** Save the current Vdbe context such that it can be restored by a ContextPop
** opcode. The context stores the last insert row id, the last statement change
** count, and the current statement change count.
................................................................................
     pc = pOp->p2 - 1;
  }
  break;
}

/* Opcode: AggReset P1 P2 P3
**
** Reset the current aggregator context so that it no longer contains any 
** data. Future aggregator elements will contain P2 values each and be sorted
** using the KeyInfo structure pointed to by P3.
**
** If P1 is non-zero, then only a single aggregator row is available (i.e.
** there is no GROUP BY expression). In this case it is illegal to invoke
** OP_AggFocus.
*/
case OP_AggReset: {
  assert( !pOp->p3 || pOp->p3type==P3_KEYINFO );
  if( pOp->p1 ){
    rc = sqlite3VdbeAggReset(0, p->pAgg, (KeyInfo *)pOp->p3);
    p->pAgg->nMem = pOp->p2;    /* Agg.nMem is used by AggInsert() */
    rc = AggInsert(p->pAgg, 0, 0);
  }else{
    rc = sqlite3VdbeAggReset(db, p->pAgg, (KeyInfo *)pOp->p3);
    p->pAgg->nMem = pOp->p2;
  }
  if( rc!=SQLITE_OK ){
    goto abort_due_to_error;
  }
  p->pAgg->apFunc = sqliteMalloc( p->pAgg->nMem*sizeof(p->pAgg->apFunc[0]) );
  if( p->pAgg->apFunc==0 ) goto no_mem;
  break;
}

/* Opcode: AggInit * P2 P3
**
** Initialize the function parameters for an aggregate function.
** The aggregate will operate out of aggregate column P2.
** P3 is a pointer to the FuncDef structure for the function.
*/
case OP_AggInit: {
  int i = pOp->p2;
  assert( i>=0 && i<p->pAgg->nMem );
  p->pAgg->apFunc[i] = (FuncDef*)pOp->p3;
  break;
}

/* Opcode: AggFunc * P2 P3
**
** Execute the step function for an aggregate.  The
** function has P2 arguments.  P3 is a pointer to the FuncDef
................................................................................
  assert( apVal || n==0 );

  for(i=0; i<n; i++, pRec++){
    apVal[i] = pRec;
    storeTypeInfo(pRec, db->enc);
  }
  i = pTos->i;
  assert( i>=0 && i<p->pAgg->nMem );
  ctx.pFunc = (FuncDef*)pOp->p3;
  pMem = &p->pAgg->pCurrent->aMem[i];
  ctx.s.z = pMem->zShort;  /* Space used for small aggregate contexts */
  ctx.pAgg = pMem->z;
  ctx.cnt = ++pMem->i;
  ctx.isError = 0;
  ctx.pColl = 0;
  if( ctx.pFunc->needCollSeq ){
    assert( pOp>p->aOp );
................................................................................
  char *zKey;
  int nKey;
  int res;
  assert( pTos>=p->aStack );
  Stringify(pTos, db->enc);
  zKey = pTos->z;
  nKey = pTos->n;
  assert( p->pAgg->pBtree );
  assert( p->pAgg->pCsr );
  rc = sqlite3BtreeMoveto(p->pAgg->pCsr, zKey, nKey, &res);
  if( rc!=SQLITE_OK ){
    goto abort_due_to_error;
  }
  if( res==0 ){
    rc = sqlite3BtreeData(p->pAgg->pCsr, 0, sizeof(AggElem*),
        (char *)&p->pAgg->pCurrent);
    pc = pOp->p2 - 1;
  }else{
    rc = AggInsert(p->pAgg, zKey, nKey);
  }
  if( rc!=SQLITE_OK ){
    goto abort_due_to_error;
  }
  Release(pTos);
  pTos--;
  break; 
................................................................................
**
** Move the top of the stack into the P2-th field of the current
** aggregate.  String values are duplicated into new memory.
*/
case OP_AggSet: {
  AggElem *pFocus;
  int i = pOp->p2;
  pFocus = p->pAgg->pCurrent;
  assert( pTos>=p->aStack );
  if( pFocus==0 ) goto no_mem;
  assert( i>=0 && i<p->pAgg->nMem );
  rc = sqlite3VdbeMemMove(&pFocus->aMem[i], pTos);
  pTos--;
  break;
}

/* Opcode: AggGet * P2 *
**
................................................................................
** Push a new entry onto the stack which is a copy of the P2-th field
** of the current aggregate.  Strings are not duplicated so
** string values will be ephemeral.
*/
case OP_AggGet: {
  AggElem *pFocus;
  int i = pOp->p2;
  pFocus = p->pAgg->pCurrent;
  if( pFocus==0 ){
    int res;
    if( sqlite3_malloc_failed ) goto no_mem;
    rc = sqlite3BtreeFirst(p->pAgg->pCsr, &res);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    if( res!=0 ){
      rc = AggInsert(p->pAgg, "", 1);
      pFocus = p->pAgg->pCurrent;
    }else{
      rc = sqlite3BtreeData(p->pAgg->pCsr, 0, 4, (char *)&pFocus);
    }
  }
  assert( i>=0 && i<p->pAgg->nMem );
  pTos++;
  sqlite3VdbeMemShallowCopy(pTos, &pFocus->aMem[i], MEM_Ephem);
  if( pTos->flags&MEM_Str ){
    sqlite3VdbeChangeEncoding(pTos, db->enc);
  }
  break;
}
................................................................................
** zero or more AggNext operations.  You must not execute an AggFocus
** in between an AggNext and an AggReset.
*/
case OP_AggNext: {
  int res;
  assert( rc==SQLITE_OK );
  CHECK_FOR_INTERRUPT;
  if( p->pAgg->searching==0 ){
    p->pAgg->searching = 1;
    if( p->pAgg->pCsr ){
      rc = sqlite3BtreeFirst(p->pAgg->pCsr, &res);
    }else{
      res = 0;
    }
  }else{
    if( p->pAgg->pCsr ){
      rc = sqlite3BtreeNext(p->pAgg->pCsr, &res);
    }else{
      res = 1;
    }
  }
  if( rc!=SQLITE_OK ) goto abort_due_to_error;
  if( res!=0 ){
    pc = pOp->p2 - 1;
  }else{
    int i;
    sqlite3_context ctx;
    Mem *aMem;

    if( p->pAgg->pCsr ){
      rc = sqlite3BtreeData(p->pAgg->pCsr, 0, sizeof(AggElem*),
          (char *)&p->pAgg->pCurrent);
      if( rc!=SQLITE_OK ) goto abort_due_to_error;
    }
    aMem = p->pAgg->pCurrent->aMem;
    for(i=0; i<p->pAgg->nMem; i++){
      FuncDef *pFunc = p->pAgg->apFunc[i];
      Mem *pMem = &aMem[i];
      if( pFunc==0 || pFunc->xFinalize==0 ) continue;
      ctx.s.flags = MEM_Null;
      ctx.s.z = pMem->zShort;
      ctx.pAgg = (void*)pMem->z;
      ctx.cnt = pMem->i;
      ctx.pFunc = pFunc;
................................................................................
  if( !pOp->p1 ){
    sqlite3ExpirePreparedStatements(db);
  }else{
    p->expired = 1;
  }
  break;
}



/* An other opcode is illegal...
*/
default: {
  sqlite3_snprintf(sizeof(zBuf),zBuf,"%d",pOp->opcode);
  sqlite3SetString(&p->zErrMsg, "unknown opcode ", zBuf, (char*)0);

*************************************************************************
** Header file for the Virtual DataBase Engine (VDBE)
**
** This header defines the interface to the virtual database engine
** or VDBE.  The VDBE implements an abstract machine that runs a
** simple program to access and modify the underlying database.
**
** $Id: vdbe.h,v 1.91 2004/09/06 17:24:13 drh Exp $
*/
#ifndef _SQLITE_VDBE_H_
#define _SQLITE_VDBE_H_
#include <stdio.h>

/*
** A single VDBE is an opaque structure named "Vdbe".  Only routines
................................................................................
void sqlite3VdbeChangeP2(Vdbe*, int addr, int P2);
void sqlite3VdbeChangeP3(Vdbe*, int addr, const char *zP1, int N);
void sqlite3VdbeDequoteP3(Vdbe*, int addr);
int sqlite3VdbeFindOp(Vdbe*, int, int, int);
VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
int sqlite3VdbeMakeLabel(Vdbe*);
void sqlite3VdbeDelete(Vdbe*);
void sqlite3VdbeMakeReady(Vdbe*,int,int,int,int);
int sqlite3VdbeFinalize(Vdbe*);
void sqlite3VdbeResolveLabel(Vdbe*, int);
int sqlite3VdbeCurrentAddr(Vdbe*);
void sqlite3VdbeTrace(Vdbe*,FILE*);
int sqlite3VdbeReset(Vdbe*);
int sqliteVdbeSetVariables(Vdbe*,int,const char**);
void sqlite3VdbeSetNumCols(Vdbe*,int);

*************************************************************************
** Header file for the Virtual DataBase Engine (VDBE)
**
** This header defines the interface to the virtual database engine
** or VDBE.  The VDBE implements an abstract machine that runs a
** simple program to access and modify the underlying database.
**
** $Id: vdbe.h,v 1.92 2005/01/29 08:32:45 danielk1977 Exp $
*/
#ifndef _SQLITE_VDBE_H_
#define _SQLITE_VDBE_H_
#include <stdio.h>

/*
** A single VDBE is an opaque structure named "Vdbe".  Only routines
................................................................................
void sqlite3VdbeChangeP2(Vdbe*, int addr, int P2);
void sqlite3VdbeChangeP3(Vdbe*, int addr, const char *zP1, int N);
void sqlite3VdbeDequoteP3(Vdbe*, int addr);
int sqlite3VdbeFindOp(Vdbe*, int, int, int);
VdbeOp *sqlite3VdbeGetOp(Vdbe*, int);
int sqlite3VdbeMakeLabel(Vdbe*);
void sqlite3VdbeDelete(Vdbe*);
void sqlite3VdbeMakeReady(Vdbe*,int,int,int,int,int);
int sqlite3VdbeFinalize(Vdbe*);
void sqlite3VdbeResolveLabel(Vdbe*, int);
int sqlite3VdbeCurrentAddr(Vdbe*);
void sqlite3VdbeTrace(Vdbe*,FILE*);
int sqlite3VdbeReset(Vdbe*);
int sqliteVdbeSetVariables(Vdbe*,int,const char**);
void sqlite3VdbeSetNumCols(Vdbe*,int);

  int nVar;           /* Number of entries in aVar[] */
  Mem *aVar;          /* Values for the OP_Variable opcode. */
  char **azVar;       /* Name of variables */
  int okVar;          /* True if azVar[] has been initialized */
  int magic;              /* Magic number for sanity checking */
  int nMem;               /* Number of memory locations currently allocated */
  Mem *aMem;              /* The memory locations */
  Agg agg;                /* Aggregate information */


  int nCallback;          /* Number of callbacks invoked so far */
  Keylist *pList;         /* A list of ROWIDs */
  int contextStackTop;    /* Index of top element in the context stack */
  int contextStackDepth;  /* The size of the "context" stack */
  Context *contextStack;  /* Stack used by opcodes ContextPush & ContextPop*/
  int pc;                 /* The program counter */
  int rc;                 /* Value to return */

  int nVar;           /* Number of entries in aVar[] */
  Mem *aVar;          /* Values for the OP_Variable opcode. */
  char **azVar;       /* Name of variables */
  int okVar;          /* True if azVar[] has been initialized */
  int magic;              /* Magic number for sanity checking */
  int nMem;               /* Number of memory locations currently allocated */
  Mem *aMem;              /* The memory locations */
  int nAgg;               /* Number of elements in apAgg */
  Agg *apAgg;             /* Array of aggregate contexts */
  Agg *pAgg;              /* Current aggregate context */
  int nCallback;          /* Number of callbacks invoked so far */
  Keylist *pList;         /* A list of ROWIDs */
  int contextStackTop;    /* Index of top element in the context stack */
  int contextStackDepth;  /* The size of the "context" stack */
  Context *contextStack;  /* Stack used by opcodes ContextPush & ContextPop*/
  int pc;                 /* The program counter */
  int rc;                 /* Value to return */

** VDBE_MAGIC_RUN.
*/
void sqlite3VdbeMakeReady(
  Vdbe *p,                       /* The VDBE */
  int nVar,                      /* Number of '?' see in the SQL statement */
  int nMem,                      /* Number of memory cells to allocate */
  int nCursor,                   /* Number of cursors to allocate */

  int isExplain                  /* True if the EXPLAIN keywords is present */
){
  int n;

  assert( p!=0 );
  assert( p->magic==VDBE_MAGIC_INIT );

................................................................................
    p->aStack = sqliteMalloc(
        n*sizeof(p->aStack[0])         /* aStack */
      + n*sizeof(Mem*)                 /* apArg */
      + nVar*sizeof(Mem)               /* aVar */
      + nVar*sizeof(char*)             /* azVar */
      + nMem*sizeof(Mem)               /* aMem */
      + nCursor*sizeof(Cursor*)        /* apCsr */

    );
    if( !sqlite3_malloc_failed ){
      p->aMem = &p->aStack[n];
      p->nMem = nMem;
      p->aVar = &p->aMem[nMem];
      p->nVar = nVar;
      p->okVar = 0;
      p->apArg = (Mem**)&p->aVar[nVar];
      p->azVar = (char**)&p->apArg[n];
      p->apCsr = (Cursor**)&p->azVar[nVar];




      p->nCursor = nCursor;
      for(n=0; n<nVar; n++){
        p->aVar[n].flags = MEM_Null;
      }
      for(n=0; n<nMem; n++){
        p->aMem[n].flags = MEM_Null;
      }
    }



  }

#ifdef SQLITE_DEBUG
  if( (p->db->flags & SQLITE_VdbeListing)!=0
    || sqlite3OsFileExists("vdbe_explain")
  ){
    int i;
    printf("VDBE Program Listing:\n");
................................................................................
** If db is not NULL, then this is being called from with an OP_AggReset
** opcode. Open the temp-table, if it has not already been opened and
** delete the contents of the table used for aggregate information, ready
** for the next round of aggregate processing.
*/
int sqlite3VdbeAggReset(sqlite3 *db, Agg *pAgg, KeyInfo *pKeyInfo){
  int rc = 0;
  BtCursor *pCsr = pAgg->pCsr;



  assert( (pCsr && pAgg->nTab>0) || (!pCsr && pAgg->nTab==0)
         || sqlite3_malloc_failed );

  /* If pCsr is not NULL, then the table used for aggregate information
  ** is open. Loop through it and free the AggElem* structure pointed at
  ** by each entry. If the finalizer has not been called for an AggElem,
  ** do that too. Finally, clear the btree table itself.
................................................................................
  if( p->contextStack ){
    for(i=0; i<p->contextStackTop; i++){
      sqlite3VdbeKeylistFree(p->contextStack[i].pList);
    }
    sqliteFree(p->contextStack);
  }
  sqlite3VdbeSorterReset(p);

  sqlite3VdbeAggReset(0, &p->agg, 0);

  p->contextStack = 0;
  p->contextStackDepth = 0;
  p->contextStackTop = 0;
  sqliteFree(p->zErrMsg);
  p->zErrMsg = 0;
}

** VDBE_MAGIC_RUN.
*/
void sqlite3VdbeMakeReady(
  Vdbe *p,                       /* The VDBE */
  int nVar,                      /* Number of '?' see in the SQL statement */
  int nMem,                      /* Number of memory cells to allocate */
  int nCursor,                   /* Number of cursors to allocate */
  int nAgg,                      /* Number of aggregate contexts required */
  int isExplain                  /* True if the EXPLAIN keywords is present */
){
  int n;

  assert( p!=0 );
  assert( p->magic==VDBE_MAGIC_INIT );

................................................................................
    p->aStack = sqliteMalloc(
        n*sizeof(p->aStack[0])         /* aStack */
      + n*sizeof(Mem*)                 /* apArg */
      + nVar*sizeof(Mem)               /* aVar */
      + nVar*sizeof(char*)             /* azVar */
      + nMem*sizeof(Mem)               /* aMem */
      + nCursor*sizeof(Cursor*)        /* apCsr */
      + nAgg*sizeof(Agg)               /* Aggregate contexts */
    );
    if( !sqlite3_malloc_failed ){
      p->aMem = &p->aStack[n];
      p->nMem = nMem;
      p->aVar = &p->aMem[nMem];
      p->nVar = nVar;
      p->okVar = 0;
      p->apArg = (Mem**)&p->aVar[nVar];
      p->azVar = (char**)&p->apArg[n];
      p->apCsr = (Cursor**)&p->azVar[nVar];
      if( nAgg>0 ){
        p->nAgg = nAgg;
        p->apAgg = (Agg*)&p->apCsr[nCursor];
      }
      p->nCursor = nCursor;
      for(n=0; n<nVar; n++){
        p->aVar[n].flags = MEM_Null;
      }


    }
  }
  p->pAgg = p->apAgg;
  for(n=0; n<p->nMem; n++){
    p->aMem[n].flags = MEM_Null;
  }

#ifdef SQLITE_DEBUG
  if( (p->db->flags & SQLITE_VdbeListing)!=0
    || sqlite3OsFileExists("vdbe_explain")
  ){
    int i;
    printf("VDBE Program Listing:\n");
................................................................................
** If db is not NULL, then this is being called from with an OP_AggReset
** opcode. Open the temp-table, if it has not already been opened and
** delete the contents of the table used for aggregate information, ready
** for the next round of aggregate processing.
*/
int sqlite3VdbeAggReset(sqlite3 *db, Agg *pAgg, KeyInfo *pKeyInfo){
  int rc = 0;
  BtCursor *pCsr;

  if( !pAgg ) return SQLITE_OK;
  pCsr = pAgg->pCsr;
  assert( (pCsr && pAgg->nTab>0) || (!pCsr && pAgg->nTab==0)
         || sqlite3_malloc_failed );

  /* If pCsr is not NULL, then the table used for aggregate information
  ** is open. Loop through it and free the AggElem* structure pointed at
  ** by each entry. If the finalizer has not been called for an AggElem,
  ** do that too. Finally, clear the btree table itself.
................................................................................
  if( p->contextStack ){
    for(i=0; i<p->contextStackTop; i++){
      sqlite3VdbeKeylistFree(p->contextStack[i].pList);
    }
    sqliteFree(p->contextStack);
  }
  sqlite3VdbeSorterReset(p);
  for(i=0; i<p->nAgg; i++){
    sqlite3VdbeAggReset(0, &p->apAgg[i], 0);
  }
  p->contextStack = 0;
  p->contextStackDepth = 0;
  p->contextStackTop = 0;
  sqliteFree(p->zErrMsg);
  p->zErrMsg = 0;
}

** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements.  This module is reponsible for
** generating the code that loops through a table looking for applicable
** rows.  Indices are selected and used to speed the search when doing
** so is applicable.  Because this module is responsible for selecting
** indices, you might also think of this module as the "query optimizer".
**
** $Id: where.c,v 1.131 2005/01/20 22:48:48 drh Exp $
*/
#include "sqliteInt.h"

/*
** The query generator uses an array of instances of this structure to
** help it analyze the subexpressions of the WHERE clause.  Each WHERE
** clause subexpression is separated from the others by an AND operator.
................................................................................
** In order for this routine to work, the calling function must have
** previously invoked sqlite3ExprResolveNames() on the expression.  See
** the header comment on that routine for additional information.
** The sqlite3ExprResolveNames() routines looks for column names and
** sets their opcodes to TK_COLUMN and their Expr.iTable fields to
** the VDBE cursor number of the table.
*/

static Bitmask exprTableUsage(ExprMaskSet *pMaskSet, Expr *p){
  Bitmask mask = 0;
  if( p==0 ) return 0;
  if( p->op==TK_COLUMN ){
    mask = getMask(pMaskSet, p->iTable);
    return mask;
  }
  if( p->pRight ){
    mask = exprTableUsage(pMaskSet, p->pRight);
  }

  if( p->pLeft ){




    mask |= exprTableUsage(pMaskSet, p->pLeft);

  }
  if( p->pList ){



    int i;


    for(i=0; i<p->pList->nExpr; i++){
      mask |= exprTableUsage(pMaskSet, p->pList->a[i].pExpr);
    }
  }
  return mask;
}

/*
** Return TRUE if the given operator is one of the operators that is
................................................................................
  int brk,            /* Jump here to abandon the loop */
  WhereLevel *pLevel  /* When level of the FROM clause we are working on */
){
  Expr *pX = pTerm->p;
  if( pX->op!=TK_IN ){
    assert( pX->op==TK_EQ );
    sqlite3ExprCode(pParse, pX->pRight);

  }else{
    int iTab = pX->iTable;
    Vdbe *v = pParse->pVdbe;



    sqlite3VdbeAddOp(v, OP_Rewind, iTab, brk);
    sqlite3VdbeAddOp(v, OP_KeyAsData, iTab, 1);

    pLevel->inP2 = sqlite3VdbeAddOp(v, OP_Column, iTab, 0);
    pLevel->inOp = OP_Next;
    pLevel->inP1 = iTab;

  }
  disableTerm(pLevel, &pTerm->p);
}

/*
** The number of bits in a Bitmask
*/

** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements.  This module is reponsible for
** generating the code that loops through a table looking for applicable
** rows.  Indices are selected and used to speed the search when doing
** so is applicable.  Because this module is responsible for selecting
** indices, you might also think of this module as the "query optimizer".
**
** $Id: where.c,v 1.132 2005/01/29 08:32:45 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** The query generator uses an array of instances of this structure to
** help it analyze the subexpressions of the WHERE clause.  Each WHERE
** clause subexpression is separated from the others by an AND operator.
................................................................................
** In order for this routine to work, the calling function must have
** previously invoked sqlite3ExprResolveNames() on the expression.  See
** the header comment on that routine for additional information.
** The sqlite3ExprResolveNames() routines looks for column names and
** sets their opcodes to TK_COLUMN and their Expr.iTable fields to
** the VDBE cursor number of the table.
*/
static Bitmask exprListTableUsage(ExprMaskSet *, ExprList *);
static Bitmask exprTableUsage(ExprMaskSet *pMaskSet, Expr *p){
  Bitmask mask = 0;
  if( p==0 ) return 0;
  if( p->op==TK_COLUMN ){
    mask = getMask(pMaskSet, p->iTable);
    return mask;
  }
  mask = exprTableUsage(pMaskSet, p->pRight);
  mask |= exprTableUsage(pMaskSet, p->pLeft);

  mask |= exprListTableUsage(pMaskSet, p->pList);
  if( p->pSelect ){
    Select *pS = p->pSelect;
    mask |= exprListTableUsage(pMaskSet, pS->pEList);
    mask |= exprListTableUsage(pMaskSet, pS->pGroupBy);
    mask |= exprListTableUsage(pMaskSet, pS->pOrderBy);
    mask |= exprTableUsage(pMaskSet, pS->pWhere);
    mask |= exprTableUsage(pMaskSet, pS->pHaving);
  }

  return mask;
}
static Bitmask exprListTableUsage(ExprMaskSet *pMaskSet, ExprList *pList){
  int i;
  Bitmask mask = 0;
  if( pList ){
    for(i=0; i<pList->nExpr; i++){
      mask |= exprTableUsage(pMaskSet, pList->a[i].pExpr);
    }
  }
  return mask;
}

/*
** Return TRUE if the given operator is one of the operators that is
................................................................................
  int brk,            /* Jump here to abandon the loop */
  WhereLevel *pLevel  /* When level of the FROM clause we are working on */
){
  Expr *pX = pTerm->p;
  if( pX->op!=TK_IN ){
    assert( pX->op==TK_EQ );
    sqlite3ExprCode(pParse, pX->pRight);
#ifndef SQLITE_OMIT_SUBQUERY
  }else{
    int iTab;
    Vdbe *v = pParse->pVdbe;

    sqlite3CodeSubselect(pParse, pX);
    iTab = pX->iTable;
    sqlite3VdbeAddOp(v, OP_Rewind, iTab, brk);
    sqlite3VdbeAddOp(v, OP_KeyAsData, iTab, 1);
    VdbeComment((v, "# %.*s", pX->span.n, pX->span.z));
    pLevel->inP2 = sqlite3VdbeAddOp(v, OP_Column, iTab, 0);
    pLevel->inOp = OP_Next;
    pLevel->inP1 = iTab;
#endif
  }
  disableTerm(pLevel, &pTerm->p);
}

/*
** The number of bits in a Bitmask
*/

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script testing the sqlite_bind API.
#
# $Id: bind.test,v 1.27 2005/01/20 02:17:02 danielk1977 Exp $
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

proc sqlite_step {stmt N VALS COLS} {
  upvar VALS vals
................................................................................
} 5
do_test bind-10.15 {
  sqlite3_bind_parameter_index $VM ?4
} 4
do_test bind-10.16 {
  sqlite3_bind_parameter_name $VM 1
} :abc
do_test bind-10.16 {
  sqlite3_bind_parameter_name $VM 2
} {}
do_test bind-10.16 {
  sqlite3_bind_parameter_name $VM 3
} {}
do_test bind-10.16 {
  sqlite3_bind_parameter_name $VM 4
} {?4}
do_test bind-10.16 {
  sqlite3_bind_parameter_name $VM 5
} :pqr
catch {sqlite3_finalize $VM}

# Make sure we catch an unterminated "(" in a Tcl-style variable name
#
ifcapable tclvar {
  do_test bind-11.1 {
    catchsql {SELECT * FROM sqlite_master WHERE name=$abc(123 and sql NOT NULL;}
  } {1 {unrecognized token: "$abc(123"}}
}

finish_test

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script testing the sqlite_bind API.
#
# $Id: bind.test,v 1.28 2005/01/29 08:32:46 danielk1977 Exp $
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

proc sqlite_step {stmt N VALS COLS} {
  upvar VALS vals
................................................................................
} 5
do_test bind-10.15 {
  sqlite3_bind_parameter_index $VM ?4
} 4
do_test bind-10.16 {
  sqlite3_bind_parameter_name $VM 1
} :abc
do_test bind-10.17 {
  sqlite3_bind_parameter_name $VM 2
} {}
do_test bind-10.18 {
  sqlite3_bind_parameter_name $VM 3
} {}
do_test bind-10.19 {
  sqlite3_bind_parameter_name $VM 4
} {?4}
do_test bind-10.20 {
  sqlite3_bind_parameter_name $VM 5
} :pqr
catch {sqlite3_finalize $VM}

# Make sure we catch an unterminated "(" in a Tcl-style variable name
#
ifcapable tclvar {
  do_test bind-11.1 {
    catchsql {SELECT * FROM sqlite_master WHERE name=$abc(123 and sql NOT NULL;}
  } {1 {unrecognized token: "$abc(123"}}
}

finish_test

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is page cache subsystem.
#
# $Id: collate3.test,v 1.9 2005/01/26 03:58:36 danielk1977 Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

#
# Tests are organised as follows:
#
................................................................................
do_test collate3-2.8 {
  catchsql {
    SELECT DISTINCT c1 FROM collate3t1;
  }
} {1 {no such collation sequence: string_compare}} 

ifcapable compound {
do_test collate3-2.9 {
  catchsql {
    SELECT c1 FROM collate3t1 UNION SELECT c1 FROM collate3t1;
  }
} {1 {no such collation sequence: string_compare}} 
do_test collate3-2.10 {
  catchsql {
    SELECT c1 FROM collate3t1 EXCEPT SELECT c1 FROM collate3t1;
  }
} {1 {no such collation sequence: string_compare}} 
do_test collate3-2.11 {
  catchsql {
    SELECT c1 FROM collate3t1 INTERSECT SELECT c1 FROM collate3t1;
  }
} {1 {no such collation sequence: string_compare}} 
do_test collate3-2.12 {
  catchsql {
    SELECT c1 FROM collate3t1 UNION ALL SELECT c1 FROM collate3t1;
  }
} {0 {}}
do_test collate3-2.13 {
  catchsql {
    SELECT 10 UNION ALL SELECT 20 ORDER BY 1 COLLATE string_compare;
  }
} {1 {no such collation sequence: string_compare}} 
do_test collate3-2.14 {
  catchsql {
    SELECT 10 INTERSECT SELECT 20 ORDER BY 1 COLLATE string_compare;
  }
} {1 {no such collation sequence: string_compare}} 
do_test collate3-2.15 {
  catchsql {
    SELECT 10 EXCEPT SELECT 20 ORDER BY 1 COLLATE string_compare;
  }
} {1 {no such collation sequence: string_compare}} 
do_test collate3-2.16 {
  catchsql {
    SELECT 10 UNION SELECT 20 ORDER BY 1 COLLATE string_compare;
  }
} {1 {no such collation sequence: string_compare}} 
do_test collate3-2.17 {
  catchsql {
    SELECT c1 FROM collate3t1 UNION ALL SELECT c1 FROM collate3t1 ORDER BY 1;
  }
} {1 {no such collation sequence: string_compare}} 
} ;# ifcapable compound

#
# Create an index that uses a collation sequence then close and
# re-open the database without re-registering the collation
# sequence. Then check that for the table with the index 
# * An INSERT fails,

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is page cache subsystem.
#
# $Id: collate3.test,v 1.10 2005/01/29 08:32:46 danielk1977 Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

#
# Tests are organised as follows:
#
................................................................................
do_test collate3-2.8 {
  catchsql {
    SELECT DISTINCT c1 FROM collate3t1;
  }
} {1 {no such collation sequence: string_compare}} 

ifcapable compound {
  do_test collate3-2.9 {
    catchsql {
      SELECT c1 FROM collate3t1 UNION SELECT c1 FROM collate3t1;
    }
  } {1 {no such collation sequence: string_compare}} 
  do_test collate3-2.10 {
    catchsql {
      SELECT c1 FROM collate3t1 EXCEPT SELECT c1 FROM collate3t1;
    }
  } {1 {no such collation sequence: string_compare}} 
  do_test collate3-2.11 {
    catchsql {
      SELECT c1 FROM collate3t1 INTERSECT SELECT c1 FROM collate3t1;
    }
  } {1 {no such collation sequence: string_compare}} 
  do_test collate3-2.12 {
    catchsql {
      SELECT c1 FROM collate3t1 UNION ALL SELECT c1 FROM collate3t1;
    }
  } {0 {}}
  do_test collate3-2.13 {
    catchsql {
      SELECT 10 UNION ALL SELECT 20 ORDER BY 1 COLLATE string_compare;
    }
  } {1 {no such collation sequence: string_compare}} 
  do_test collate3-2.14 {
    catchsql {
      SELECT 10 INTERSECT SELECT 20 ORDER BY 1 COLLATE string_compare;
    }
  } {1 {no such collation sequence: string_compare}} 
  do_test collate3-2.15 {
    catchsql {
      SELECT 10 EXCEPT SELECT 20 ORDER BY 1 COLLATE string_compare;
    }
  } {1 {no such collation sequence: string_compare}} 
  do_test collate3-2.16 {
    catchsql {
      SELECT 10 UNION SELECT 20 ORDER BY 1 COLLATE string_compare;
    }
  } {1 {no such collation sequence: string_compare}} 
  do_test collate3-2.17 {
    catchsql {
      SELECT c1 FROM collate3t1 UNION ALL SELECT c1 FROM collate3t1 ORDER BY 1;
    }
  } {1 {no such collation sequence: string_compare}} 
} ;# ifcapable compound

#
# Create an index that uses a collation sequence then close and
# re-open the database without re-registering the collation
# sequence. Then check that for the table with the index 
# * An INSERT fails,

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing corner cases of the INSERT statement.
#
# $Id: insert3.test,v 1.2 2005/01/15 00:36:37 drh Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# All the tests in this file require trigger support
#
ifcapable {trigger} {
................................................................................
  }
} {5 2 453 1 hello 2}
do_test insert3-1.3 {
  execsql {
    SELECT * FROM log2 ORDER BY x;
  }
} {hi 1}

do_test insert3-1.4 {
  execsql {
    INSERT INTO t1 SELECT * FROM t1;

    SELECT 'a:', x, y FROM log UNION ALL SELECT 'b:', x, y FROM log2 ORDER BY x;
  }
} {a: 5 4 b: 10 2 b: 20 1 a: 453 2 a: hello 4 b: hi 2 b: world 1}
do_test insert3-1.5 {
  execsql {
    INSERT INTO t1(a) VALUES('xyz');
    SELECT * FROM log ORDER BY x;
  }
} {5 4 453 2 hello 4 xyz 1}


do_test insert3-2.1 {
  execsql {
    CREATE TABLE t2(
      a INTEGER PRIMARY KEY,
      b DEFAULT 'b',
      c DEFAULT 'c'

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing corner cases of the INSERT statement.
#
# $Id: insert3.test,v 1.3 2005/01/29 08:32:46 danielk1977 Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# All the tests in this file require trigger support
#
ifcapable {trigger} {
................................................................................
  }
} {5 2 453 1 hello 2}
do_test insert3-1.3 {
  execsql {
    SELECT * FROM log2 ORDER BY x;
  }
} {hi 1}
ifcapable compound {
  do_test insert3-1.4 {
    execsql {
      INSERT INTO t1 SELECT * FROM t1;
      SELECT 'a:', x, y FROM log UNION ALL 
          SELECT 'b:', x, y FROM log2 ORDER BY x;
    }
  } {a: 5 4 b: 10 2 b: 20 1 a: 453 2 a: hello 4 b: hi 2 b: world 1}
  do_test insert3-1.5 {
    execsql {
      INSERT INTO t1(a) VALUES('xyz');
      SELECT * FROM log ORDER BY x;
    }
  } {5 4 453 2 hello 4 xyz 1}
}

do_test insert3-2.1 {
  execsql {
    CREATE TABLE t2(
      a INTEGER PRIMARY KEY,
      b DEFAULT 'b',
      c DEFAULT 'c'

#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# This file implements tests for miscellanous features that were
# left out of other test files.
#
# $Id: misc4.test,v 1.13 2005/01/21 03:12:16 danielk1977 Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Prepare a statement that will create a temporary table.  Then do
# a rollback.  Then try to execute the prepared statement.
#
................................................................................
      insert into b values ('+1',4);
      
      select a.*, x.*
        from a, (select key,sum(period) from b group by key) as x
        where a.key=x.key;
    }
  } {01 data01 01 3.0 +1 data+1 +1 7.0}
}














# Ticket #1036.  When creating tables from a SELECT on a view, use the
# short names of columns.
#
ifcapable view {
  do_test misc4-5.1 {
    execsql {

#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# This file implements tests for miscellanous features that were
# left out of other test files.
#
# $Id: misc4.test,v 1.14 2005/01/29 08:32:46 danielk1977 Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Prepare a statement that will create a temporary table.  Then do
# a rollback.  Then try to execute the prepared statement.
#
................................................................................
      insert into b values ('+1',4);
      
      select a.*, x.*
        from a, (select key,sum(period) from b group by key) as x
        where a.key=x.key;
    }
  } {01 data01 01 3.0 +1 data+1 +1 7.0}

  # This test case tests the same property as misc4-4.1, but it is
  # a bit smaller which makes it easier to work with while debugging.
  do_test misc4-4.2 {
    execsql {
      CREATE TABLE ab(a TEXT, b TEXT);
      INSERT INTO ab VALUES('01', '1');
    }
    execsql {
      select * from ab, (select b from ab) as x where x.b = ab.a;
    }
  } {}
}


# Ticket #1036.  When creating tables from a SELECT on a view, use the
# short names of columns.
#
ifcapable view {
  do_test misc4-5.1 {
    execsql {

#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing SELECT statements that contain
# subqueries in their FROM clause.
#
# $Id: select6.test,v 1.16 2005/01/21 03:12:16 danielk1977 Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Omit this whole file if the library is build without subquery support.
ifcapable !subquery {
  finish_test
................................................................................
    SELECT a.q, a.p, b.r
    FROM (SELECT count(*) as p , b as q FROM t2 GROUP BY q) AS a,
         (SELECT max(a) as r, b as s FROM t2 GROUP BY s) as b
    WHERE a.q=b.s ORDER BY a.q
  }
} {1 1 1 2 2 3 3 4 7 4 8 15 5 5 20}

do_test sqlite6-3.1 {
  execsql2 {
    SELECT * FROM (SELECT * FROM (SELECT * FROM t1 WHERE x=3));
  }
} {x 3 y 2}
do_test sqlite6-3.2 {
  execsql {
    SELECT * FROM
      (SELECT a.q, a.p, b.r
       FROM (SELECT count(*) as p , b as q FROM t2 GROUP BY q) AS a,
            (SELECT max(a) as r, b as s FROM t2 GROUP BY s) as b
       WHERE a.q=b.s ORDER BY a.q)
    ORDER BY q
  }
} {1 1 1 2 2 3 3 4 7 4 8 15 5 5 20}
do_test select6-3.3 {
  execsql {
    SELECT a,b,a+b FROM (SELECT avg(x) as 'a', avg(y) as 'b' FROM t1)
  }
} {10.5 3.7 14.2}

#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing SELECT statements that contain
# subqueries in their FROM clause.
#
# $Id: select6.test,v 1.17 2005/01/29 08:32:46 danielk1977 Exp $

set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Omit this whole file if the library is build without subquery support.
ifcapable !subquery {
  finish_test
................................................................................
    SELECT a.q, a.p, b.r
    FROM (SELECT count(*) as p , b as q FROM t2 GROUP BY q) AS a,
         (SELECT max(a) as r, b as s FROM t2 GROUP BY s) as b
    WHERE a.q=b.s ORDER BY a.q
  }
} {1 1 1 2 2 3 3 4 7 4 8 15 5 5 20}

do_test select6-3.1 {
  execsql2 {
    SELECT * FROM (SELECT * FROM (SELECT * FROM t1 WHERE x=3));
  }
} {x 3 y 2}
do_test select6-3.2 {
  execsql {
    SELECT * FROM
      (SELECT a.q, a.p, b.r
       FROM (SELECT count(*) as p , b as q FROM t2 GROUP BY q) AS a,
            (SELECT max(a) as r, b as s FROM t2 GROUP BY s) as b
       WHERE a.q=b.s ORDER BY a.q)
    ORDER BY "a.q"
  }
} {1 1 1 2 2 3 3 4 7 4 8 15 5 5 20}
do_test select6-3.3 {
  execsql {
    SELECT a,b,a+b FROM (SELECT avg(x) as 'a', avg(y) as 'b' FROM t1)
  }
} {10.5 3.7 14.2}

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#*************************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is testing correlated subqueries
#
# $Id: subquery.test,v 1.2 2005/01/21 11:55:28 danielk1977 Exp $
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

ifcapable !subquery {
  finish_test
................................................................................
} {3}
do_test subquery-1.4 {
  execsql {
    SELECT b FROM t1 WHERE NOT EXISTS(SELECT * FROM t2 WHERE y=a)
  }
} {13 31 57}


















































































































































































finish_test

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#*************************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is testing correlated subqueries
#
# $Id: subquery.test,v 1.3 2005/01/29 08:32:47 danielk1977 Exp $
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl

ifcapable !subquery {
  finish_test
................................................................................
} {3}
do_test subquery-1.4 {
  execsql {
    SELECT b FROM t1 WHERE NOT EXISTS(SELECT * FROM t2 WHERE y=a)
  }
} {13 31 57}

# Simple tests to make sure correlated subqueries in WHERE clauses
# are used by the query optimizer correctly.
do_test subquery-1.5 {
  execsql {
    SELECT a, x FROM t1, t2 WHERE t1.a = (SELECT x);
  }
} {1 1 3 3 5 5 7 7}
do_test subquery-1.6 {
  execsql {
    CREATE INDEX i1 ON t1(a);
    SELECT a, x FROM t1, t2 WHERE t1.a = (SELECT x);
  }
} {1 1 3 3 5 5 7 7}
do_test subquery-1.7 {
  execsql {
    SELECT a, x FROM t2, t1 WHERE t1.a = (SELECT x);
  }
} {1 1 3 3 5 5 7 7}

# Try an aggregate in both the subquery and the parent query.
do_test subquery-1.6 {
  execsql {
    SELECT count(*) FROM t1 WHERE a > (SELECT count(*) FROM t2);
  }
} {2}


#------------------------------------------------------------------
# The following test cases - subquery-2.* - are not logically
# organized. They're here largely because they were failing during
# one stage of development of sub-queries.
#
do_test subquery-2.1 {
  execsql {
    SELECT (SELECT 10);
  }
} {10}
do_test subquery-2.2.1 {
  execsql {
    CREATE TABLE t3(a PRIMARY KEY, b);
    INSERT INTO t3 VALUES(1, 2);
    INSERT INTO t3 VALUES(3, 1);
  }
} {}
do_test subquery-2.2.2 {
  execsql {
    SELECT * FROM t3 WHERE a IN (SELECT b FROM t3);
  }
} {1 2}
do_test subquery-2.2.3 {
  execsql {
    DROP TABLE t3;
  }
} {}
do_test subquery-2.3.1 {
  execsql {
    CREATE TABLE t3(a TEXT);
    INSERT INTO t3 VALUES('10');
  }
} {}
do_test subquery-2.3.2 {
  execsql {
    SELECT a IN (10.0, 20) FROM t3;
  }
} {0}
do_test subquery-2.3.3 {
  execsql {
    DROP TABLE t3;
  }
} {}
do_test subquery-2.4.1 {
  execsql {
    CREATE TABLE t3(a TEXT);
    INSERT INTO t3 VALUES('XX');
  }
} {}
do_test subquery-2.4.2 {
  execsql {
    SELECT count(*) FROM t3 WHERE a IN (SELECT 'XX')
  }
} {1}
do_test subquery-2.4.3 {
  execsql {
    DROP TABLE t3;
  }
} {}
do_test subquery-2.5.1 {
  execsql {
    CREATE TABLE t3(a INTEGER);
    INSERT INTO t3 VALUES(10);

    CREATE TABLE t4(x TEXT);
    INSERT INTO t4 VALUES('10.0');
  }
} {}
do_test subquery-2.5.2 {
  execsql {
    SELECT * FROM t4 WHERE x IN (SELECT a FROM t3);
  }
} {10.0}
do_test subquery-2.5.3 {
  execsql {
    CREATE INDEX t4i ON t4(x);
    SELECT * FROM t4 WHERE x IN (SELECT a FROM t3);
  }
} {10.0}
do_test subquery-2.5.4 {
  execsql {
    DROP TABLE t3;
    DROP TABLE t4;
  }
} {}

#------------------------------------------------------------------
# The following test cases - subquery-3.* - test tickets that
# were raised during development of correlated subqueries.
#

# Ticket 1083
ifcapable view {
  do_test subquery-3.1 {
    catchsql { DROP TABLE t1; }
    catchsql { DROP TABLE t2; }
    execsql {
      CREATE TABLE t1(a,b);
      INSERT INTO t1 VALUES(1,2);
      CREATE VIEW v1 AS SELECT b FROM t1 WHERE a>0;
      CREATE TABLE t2(p,q);
      INSERT INTO t2 VALUES(2,9);
      SELECT * FROM v1 WHERE EXISTS(SELECT * FROM t2 WHERE p=v1.b);
    }
  } {2}
}

# Ticket 1084
do_test subquery-3.2 {
  catchsql {
    CREATE TABLE t1(a,b);
    INSERT INTO t1 VALUES(1,2);
  }
  execsql {
    SELECT (SELECT t1.a) FROM t1;
  }
} {1}

#------------------------------------------------------------------
# These tests - subquery-4.* - use the TCL statement cache to try 
# and expose bugs to do with re-using statements that have been 
# passed to sqlite3_reset().
#
# One problem was that VDBE memory cells were not being initialised
# to NULL on the second and subsequent executions.
#
do_test subquery-4.1.1 {
  execsql {
    SELECT (SELECT a FROM t1);
  }
} {1}
do_test subquery-4.2 {
  execsql {
    DELETE FROM t1;
    SELECT (SELECT a FROM t1);
  }
} {{}}
do_test subquery-4.2.1 {
  execsql {
    CREATE TABLE t3(a PRIMARY KEY);
    INSERT INTO t3 VALUES(10);
  }
  execsql {INSERT INTO t3 VALUES((SELECT max(a) FROM t3)+1)}
} {}
do_test subquery-4.2.2 {
  execsql {INSERT INTO t3 VALUES((SELECT max(a) FROM t3)+1)}
} {}



finish_test

        SELECT * FROM clog ORDER BY idx;
      }] {
        lappend r [expr {int($v)}]
      }
      set r
    } [list 1 1 2  4  6 10 20 \
            2 1 2 13 24 10 20 \
  	  3 3 4 13 24 30 40 \
  	  4 3 4 40 60 30 40 \
            1 1 2 13 24 10 20 ]
  
    execsql {
      DELETE FROM rlog;
      DELETE FROM tbl;
      INSERT INTO tbl VALUES (100, 100);
      INSERT INTO tbl VALUES (300, 200);

        SELECT * FROM clog ORDER BY idx;
      }] {
        lappend r [expr {int($v)}]
      }
      set r
    } [list 1 1 2  4  6 10 20 \
            2 1 2 13 24 10 20 \
  	    3 3 4 13 24 30 40 \
  	    4 3 4 40 60 30 40 \
            1 1 2 13 24 10 20 ]
  
    execsql {
      DELETE FROM rlog;
      DELETE FROM tbl;
      INSERT INTO tbl VALUES (100, 100);
      INSERT INTO tbl VALUES (300, 200);

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing VIEW statements.
#
# $Id: view.test,v 1.22 2005/01/21 04:25:47 danielk1977 Exp $
set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Omit this entire file if the library is not configured with views enabled.
ifcapable !view {
  finish_test
  return
................................................................................
ifcapable compound {
do_test  view-3.4 {
  execsql2 {
    CREATE VIEW v3 AS SELECT a FROM t1 UNION SELECT b FROM t1 ORDER BY b;
    SELECT * FROM v3 LIMIT 4;
  }
} {b 2 b 3 b 5 b 6}
do_test  view-3.5 {
  execsql2 {
    CREATE VIEW v4 AS 
      SELECT a, b FROM t1 
      UNION
      SELECT b AS 'x', a AS 'y' FROM t1
      ORDER BY x, y;
    SELECT y FROM v4 ORDER BY y LIMIT 4;

#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing VIEW statements.
#
# $Id: view.test,v 1.23 2005/01/29 08:32:47 danielk1977 Exp $
set testdir [file dirname $argv0]
source $testdir/tester.tcl

# Omit this entire file if the library is not configured with views enabled.
ifcapable !view {
  finish_test
  return
................................................................................
ifcapable compound {
do_test  view-3.4 {
  execsql2 {
    CREATE VIEW v3 AS SELECT a FROM t1 UNION SELECT b FROM t1 ORDER BY b;
    SELECT * FROM v3 LIMIT 4;
  }
} {b 2 b 3 b 5 b 6}
do_test view-3.5 {
  execsql2 {
    CREATE VIEW v4 AS 
      SELECT a, b FROM t1 
      UNION
      SELECT b AS 'x', a AS 'y' FROM t1
      ORDER BY x, y;
    SELECT y FROM v4 ORDER BY y LIMIT 4;