** a legal notice, here is a blessing:
**
**    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.
**
*************************************************************************
** $Id: btree.c,v 1.242 2005/01/21 00:22:38 drh Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
**
**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
**     "Sorting And Searching", pages 473-480. Addison-Wesley
**     Publishing Company, Reading, Massachusetts.
................................................................................
** Change the way data is synced to disk in order to increase or decrease
** how well the database resists damage due to OS crashes and power
** failures.  Level 1 is the same as asynchronous (no syncs() occur and
** there is a high probability of damage)  Level 2 is the default.  There
** is a very low but non-zero probability of damage.  Level 3 reduces the
** probability of damage to near zero but with a write performance reduction.
*/

int sqlite3BtreeSetSafetyLevel(Btree *pBt, int level){
  sqlite3pager_set_safety_level(pBt->pPager, level);
  return SQLITE_OK;
}


/*
** Change the default pages size and the number of reserved bytes per page.
**
** The page size must be a power of 2 between 512 and 65536.  If the page
** size supplied does not meet this constraint then the page size is not
** changed.

** a legal notice, here is a blessing:
**
**    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.
**
*************************************************************************
** $Id: btree.c,v 1.243 2005/01/21 08:13:14 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** For a detailed discussion of BTrees, refer to
**
**     Donald E. Knuth, THE ART OF COMPUTER PROGRAMMING, Volume 3:
**     "Sorting And Searching", pages 473-480. Addison-Wesley
**     Publishing Company, Reading, Massachusetts.
................................................................................
** Change the way data is synced to disk in order to increase or decrease
** how well the database resists damage due to OS crashes and power
** failures.  Level 1 is the same as asynchronous (no syncs() occur and
** there is a high probability of damage)  Level 2 is the default.  There
** is a very low but non-zero probability of damage.  Level 3 reduces the
** probability of damage to near zero but with a write performance reduction.
*/
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
int sqlite3BtreeSetSafetyLevel(Btree *pBt, int level){
  sqlite3pager_set_safety_level(pBt->pPager, level);
  return SQLITE_OK;
}
#endif

/*
** Change the default pages size and the number of reserved bytes per page.
**
** The page size must be a power of 2 between 512 and 65536.  If the page
** size supplied does not meet this constraint then the page size is not
** changed.

**    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 1.186 2005/01/20 22:48:48 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**
................................................................................
    pItem->zName = sqliteStrDup(pOldItem->zName);
    pItem->sortOrder = pOldItem->sortOrder;
    pItem->isAgg = pOldItem->isAgg;
    pItem->done = 0;
  }
  return pNew;
}









SrcList *sqlite3SrcListDup(SrcList *p){
  SrcList *pNew;
  int i;
  int nByte;
  if( p==0 ) return 0;
  nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
  pNew = sqliteMallocRaw( nByte );
................................................................................
  pNew->nOffset = p->nOffset;
  pNew->iLimit = -1;
  pNew->iOffset = -1;
  pNew->ppOpenTemp = 0;
  pNew->pFetch = 0;
  return pNew;
}








/*
** Add a new element to the end of an expression list.  If pList is
** initially NULL, then create a new expression list.
*/
ExprList *sqlite3ExprListAppend(ExprList *pList, Expr *pExpr, Token *pName){
................................................................................
        sqlite3VdbeAddOp(v, OP_Gosub, 0, pExpr->iTable);
        VdbeComment((v, "# run subquery"));
      }
      sqlite3VdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);
      VdbeComment((v, "# load subquery result"));
      break;
    }
#endif
    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.
................................................................................
      sqlite3VdbeAddOp(v, OP_Goto, 0, addr+7);
      sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, &affinity, 1);   /* addr + 4 */
      sqlite3VdbeAddOp(v, OP_Found, pExpr->iTable, addr+7);
      sqlite3VdbeAddOp(v, OP_AddImm, -1, 0);                  /* addr + 6 */

      break;
    }

    case TK_BETWEEN: {
      Expr *pLeft = pExpr->pLeft;
      struct ExprList_item *pLItem = pExpr->pList->a;
      Expr *pRight = pLItem->pExpr;
      sqlite3ExprCode(pParse, pLeft);
      sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
      sqlite3ExprCode(pParse, pRight);
................................................................................
      }
    }
#endif
    break;
  }
}


/*
** Generate code that evalutes the given expression and leaves the result
** on the stack.  See also sqlite3ExprCode().
**
** This routine might also cache the result and modify the pExpr tree
** so that it will make use of the cached result on subsequent evaluations
** rather than evaluate the whole expression again.  Trivial expressions are
................................................................................
  addr2 = sqlite3VdbeCurrentAddr(v);
  if( addr2>addr1+1 || sqlite3VdbeGetOp(v, addr1)->opcode==OP_Function ){
    iMem = pExpr->iTable = pParse->nMem++;
    sqlite3VdbeAddOp(v, OP_MemStore, iMem, 0);
    pExpr->op = TK_REGISTER;
  }
}


/*
** Generate code that pushes the value of every element of the given
** expression list onto the stack.
**
** Return the number of elements pushed onto the stack.
*/

**    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 1.187 2005/01/21 08:13:15 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**
................................................................................
    pItem->zName = sqliteStrDup(pOldItem->zName);
    pItem->sortOrder = pOldItem->sortOrder;
    pItem->isAgg = pOldItem->isAgg;
    pItem->done = 0;
  }
  return pNew;
}

/*
** If cursors, triggers, views and subqueries are all omitted from
** the build, then none of the following routines, except for 
** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes
** called with a NULL argument.
*/
#if !defined(SQLITE_OMIT_CURSOR) || !defined(SQLITE_OMIT_VIEW) \
 || !defined(SQLITE_OMIT_TRIGGER) || !defined(SQLITE_OMIT_SUBQUERY)
SrcList *sqlite3SrcListDup(SrcList *p){
  SrcList *pNew;
  int i;
  int nByte;
  if( p==0 ) return 0;
  nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
  pNew = sqliteMallocRaw( nByte );
................................................................................
  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;
}
#endif


/*
** Add a new element to the end of an expression list.  If pList is
** initially NULL, then create a new expression list.
*/
ExprList *sqlite3ExprListAppend(ExprList *pList, Expr *pExpr, Token *pName){
................................................................................
        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.
................................................................................
      sqlite3VdbeAddOp(v, OP_Goto, 0, addr+7);
      sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, &affinity, 1);   /* addr + 4 */
      sqlite3VdbeAddOp(v, OP_Found, pExpr->iTable, addr+7);
      sqlite3VdbeAddOp(v, OP_AddImm, -1, 0);                  /* addr + 6 */

      break;
    }
#endif
    case TK_BETWEEN: {
      Expr *pLeft = pExpr->pLeft;
      struct ExprList_item *pLItem = pExpr->pList->a;
      Expr *pRight = pLItem->pExpr;
      sqlite3ExprCode(pParse, pLeft);
      sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
      sqlite3ExprCode(pParse, pRight);
................................................................................
      }
    }
#endif
    break;
  }
}

#ifndef SQLITE_OMIT_TRIGGER
/*
** Generate code that evalutes the given expression and leaves the result
** on the stack.  See also sqlite3ExprCode().
**
** This routine might also cache the result and modify the pExpr tree
** so that it will make use of the cached result on subsequent evaluations
** rather than evaluate the whole expression again.  Trivial expressions are
................................................................................
  addr2 = sqlite3VdbeCurrentAddr(v);
  if( addr2>addr1+1 || sqlite3VdbeGetOp(v, addr1)->opcode==OP_Function ){
    iMem = pExpr->iTable = pParse->nMem++;
    sqlite3VdbeAddOp(v, OP_MemStore, iMem, 0);
    pExpr->op = TK_REGISTER;
  }
}
#endif

/*
** Generate code that pushes the value of every element of the given
** expression list onto the stack.
**
** Return the number of elements pushed onto the stack.
*/

**
*************************************************************************
** 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 1.272 2005/01/18 16:02:40 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** The following constant value is used by the SQLITE_BIGENDIAN and
................................................................................
      (!xFunc && (xFinal && !xStep)) ||
      (!xFunc && (!xFinal && xStep)) ||
      (nArg<-1 || nArg>127) ||
      (255<(nName = strlen(zFunctionName))) ){
    return SQLITE_ERROR;
  }
  

  /* If SQLITE_UTF16 is specified as the encoding type, transform this
  ** to one of SQLITE_UTF16LE or SQLITE_UTF16BE using the
  ** SQLITE_UTF16NATIVE macro. SQLITE_UTF16 is not used internally.
  **
  ** If SQLITE_ANY is specified, add three versions of the function
  ** to the hash table.
  */
................................................................................
         pUserData, xFunc, xStep, xFinal);
    if( rc!=SQLITE_OK ) return rc;
    rc = sqlite3_create_function(db, zFunctionName, nArg, SQLITE_UTF16LE,
        pUserData, xFunc, xStep, xFinal);
    if( rc!=SQLITE_OK ) return rc;
    enc = SQLITE_UTF16BE;
  }




  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, enc, 1);
  if( p==0 ) return SQLITE_NOMEM;
  p->xFunc = xFunc;
  p->xStep = xStep;
  p->xFinalize = xFinal;
  p->pUserData = pUserData;
  return SQLITE_OK;
}

int sqlite3_create_function16(
  sqlite3 *db,
  const void *zFunctionName,
  int nArg,
  int eTextRep,
  void *pUserData,
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
................................................................................
  if( !zFunc8 ){
    return SQLITE_NOMEM;
  }
  rc = sqlite3_create_function(db, zFunc8, nArg, eTextRep, 
      pUserData, xFunc, xStep, xFinal);
  return rc;
}


/*
** Register a trace function.  The pArg from the previously registered trace
** is returned.  
**
** A NULL trace function means that no tracing is executes.  A non-NULL
** trace is a pointer to a function that is invoked at the start of each
................................................................................
  }
  if( sParse.rc==SQLITE_SCHEMA ){
    sqlite3ResetInternalSchema(db, 0);
  }
  if( pzTail ) *pzTail = sParse.zTail;
  rc = sParse.rc;


  if( rc==SQLITE_OK && sParse.pVdbe && sParse.explain ){
    sqlite3VdbeSetNumCols(sParse.pVdbe, 5);
    sqlite3VdbeSetColName(sParse.pVdbe, 0, "addr", P3_STATIC);
    sqlite3VdbeSetColName(sParse.pVdbe, 1, "opcode", P3_STATIC);
    sqlite3VdbeSetColName(sParse.pVdbe, 2, "p1", P3_STATIC);
    sqlite3VdbeSetColName(sParse.pVdbe, 3, "p2", P3_STATIC);
    sqlite3VdbeSetColName(sParse.pVdbe, 4, "p3", P3_STATIC);
  } 


prepare_out:
  if( sqlite3SafetyOff(db) ){
    rc = SQLITE_MISUSE;
  }
  if( rc==SQLITE_OK ){
    *ppStmt = (sqlite3_stmt*)sParse.pVdbe;

**
*************************************************************************
** 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 1.273 2005/01/21 08:13:15 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** The following constant value is used by the SQLITE_BIGENDIAN and
................................................................................
      (!xFunc && (xFinal && !xStep)) ||
      (!xFunc && (!xFinal && xStep)) ||
      (nArg<-1 || nArg>127) ||
      (255<(nName = strlen(zFunctionName))) ){
    return SQLITE_ERROR;
  }
  
#ifndef SQLITE_OMIT_UTF16
  /* If SQLITE_UTF16 is specified as the encoding type, transform this
  ** to one of SQLITE_UTF16LE or SQLITE_UTF16BE using the
  ** SQLITE_UTF16NATIVE macro. SQLITE_UTF16 is not used internally.
  **
  ** If SQLITE_ANY is specified, add three versions of the function
  ** to the hash table.
  */
................................................................................
         pUserData, xFunc, xStep, xFinal);
    if( rc!=SQLITE_OK ) return rc;
    rc = sqlite3_create_function(db, zFunctionName, nArg, SQLITE_UTF16LE,
        pUserData, xFunc, xStep, xFinal);
    if( rc!=SQLITE_OK ) return rc;
    enc = SQLITE_UTF16BE;
  }
#else
  enc = SQLITE_UTF8;
#endif

  p = sqlite3FindFunction(db, zFunctionName, nName, nArg, enc, 1);
  if( p==0 ) return SQLITE_NOMEM;
  p->xFunc = xFunc;
  p->xStep = xStep;
  p->xFinalize = xFinal;
  p->pUserData = pUserData;
  return SQLITE_OK;
}
#ifndef SQLITE_OMIT_UTF16
int sqlite3_create_function16(
  sqlite3 *db,
  const void *zFunctionName,
  int nArg,
  int eTextRep,
  void *pUserData,
  void (*xFunc)(sqlite3_context*,int,sqlite3_value**),
................................................................................
  if( !zFunc8 ){
    return SQLITE_NOMEM;
  }
  rc = sqlite3_create_function(db, zFunc8, nArg, eTextRep, 
      pUserData, xFunc, xStep, xFinal);
  return rc;
}
#endif

/*
** Register a trace function.  The pArg from the previously registered trace
** is returned.  
**
** A NULL trace function means that no tracing is executes.  A non-NULL
** trace is a pointer to a function that is invoked at the start of each
................................................................................
  }
  if( sParse.rc==SQLITE_SCHEMA ){
    sqlite3ResetInternalSchema(db, 0);
  }
  if( pzTail ) *pzTail = sParse.zTail;
  rc = sParse.rc;

#ifndef SQLITE_OMIT_EXPLAIN
  if( rc==SQLITE_OK && sParse.pVdbe && sParse.explain ){
    sqlite3VdbeSetNumCols(sParse.pVdbe, 5);
    sqlite3VdbeSetColName(sParse.pVdbe, 0, "addr", P3_STATIC);
    sqlite3VdbeSetColName(sParse.pVdbe, 1, "opcode", P3_STATIC);
    sqlite3VdbeSetColName(sParse.pVdbe, 2, "p1", P3_STATIC);
    sqlite3VdbeSetColName(sParse.pVdbe, 3, "p2", P3_STATIC);
    sqlite3VdbeSetColName(sParse.pVdbe, 4, "p3", P3_STATIC);
  } 
#endif

prepare_out:
  if( sqlite3SafetyOff(db) ){
    rc = SQLITE_MISUSE;
  }
  if( rc==SQLITE_OK ){
    *ppStmt = (sqlite3_stmt*)sParse.pVdbe;

** 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 1.184 2005/01/20 11:32:24 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>

................................................................................
**              single disk sector is atomic, then this mode provides
**              assurance that the journal will not be corrupted to the
**              point of causing damage to the database during rollback.
**
** Numeric values associated with these states are OFF==1, NORMAL=2,
** and FULL=3.
*/

void sqlite3pager_set_safety_level(Pager *pPager, int level){
  pPager->noSync =  level==1 || pPager->tempFile;
  pPager->fullSync = level==3 && !pPager->tempFile;
  if( pPager->noSync ) pPager->needSync = 0;
}


/*
** Open a temporary file.  Write the name of the file into zName
** (zName must be at least SQLITE_TEMPNAME_SIZE bytes long.)  Write
** the file descriptor into *fd.  Return SQLITE_OK on success or some
** other error code if we fail.
**
................................................................................
    assert( pPager->aInStmt!=0 );
    pPager->aInStmt[pPg->pgno/8] |= 1<<(pPg->pgno&7);
    page_add_to_stmt_list(pPg);
  }
}



/*
** Clear a PgHistory block
*/
static void clearHistory(PgHistory *pHist){
  sqliteFree(pHist->pOrig);
  sqliteFree(pHist->pStmt);
  pHist->pOrig = 0;
  pHist->pStmt = 0;
}




/*
** Commit all changes to the database and release the write lock.
**
** If the commit fails for any reason, a rollback attempt is made
** and an error code is returned.  If the commit worked, SQLITE_OK
** is returned.
................................................................................
  return pPager->fd->fd.locktype;
#else
  return pPager->fd.locktype;
#endif
}
#endif

#ifdef SQLITE_TEST
/*
** Print a listing of all referenced pages and their ref count.
*/
void sqlite3pager_refdump(Pager *pPager){
  PgHdr *pPg;
  for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
    if( pPg->nRef<=0 ) continue;
    sqlite3DebugPrintf("PAGE %3d addr=%p nRef=%d\n", 
       pPg->pgno, PGHDR_TO_DATA(pPg), pPg->nRef);
  }
}
#endif

** 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 1.185 2005/01/21 08:13:15 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include "pager.h"
#include <assert.h>
#include <string.h>

................................................................................
**              single disk sector is atomic, then this mode provides
**              assurance that the journal will not be corrupted to the
**              point of causing damage to the database during rollback.
**
** Numeric values associated with these states are OFF==1, NORMAL=2,
** and FULL=3.
*/
#ifndef SQLITE_OMIT_PAGER_PRAGMAS
void sqlite3pager_set_safety_level(Pager *pPager, int level){
  pPager->noSync =  level==1 || pPager->tempFile;
  pPager->fullSync = level==3 && !pPager->tempFile;
  if( pPager->noSync ) pPager->needSync = 0;
}
#endif

/*
** Open a temporary file.  Write the name of the file into zName
** (zName must be at least SQLITE_TEMPNAME_SIZE bytes long.)  Write
** the file descriptor into *fd.  Return SQLITE_OK on success or some
** other error code if we fail.
**
................................................................................
    assert( pPager->aInStmt!=0 );
    pPager->aInStmt[pPg->pgno/8] |= 1<<(pPg->pgno&7);
    page_add_to_stmt_list(pPg);
  }
}


#ifndef SQLITE_OMIT_MEMORYDB
/*
** Clear a PgHistory block
*/
static void clearHistory(PgHistory *pHist){
  sqliteFree(pHist->pOrig);
  sqliteFree(pHist->pStmt);
  pHist->pOrig = 0;
  pHist->pStmt = 0;
}
#else
#define clearHistory(x)
#endif

/*
** Commit all changes to the database and release the write lock.
**
** If the commit fails for any reason, a rollback attempt is made
** and an error code is returned.  If the commit worked, SQLITE_OK
** is returned.
................................................................................
  return pPager->fd->fd.locktype;
#else
  return pPager->fd.locktype;
#endif
}
#endif

#ifdef SQLITE_DEBUG
/*
** Print a listing of all referenced pages and their ref count.
*/
void sqlite3pager_refdump(Pager *pPager){
  PgHdr *pPg;
  for(pPg=pPager->pAll; pPg; pPg=pPg->pNextAll){
    if( pPg->nRef<=0 ) continue;
    sqlite3DebugPrintf("PAGE %3d addr=%p nRef=%d\n", 
       pPg->pgno, PGHDR_TO_DATA(pPg), pPg->nRef);
  }
}
#endif

**    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 1.232 2005/01/20 22:48:48 drh Exp $
*/
#include "sqliteInt.h"


/*
** Allocate a new Select structure and return a pointer to that
** structure.
................................................................................
        sqlite3VdbeAddOp(v, OP_NewRecno, iParm, 0);
        sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
        sqlite3VdbeAddOp(v, OP_PutIntKey, iParm, 0);
      }
      break;
    }


    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
    ** then there should be a single item on the stack.  Write this
    ** item into the set table with bogus data.
    */
    case SRT_Set: {
      int addr1 = sqlite3VdbeCurrentAddr(v);
      int addr2;
................................................................................
        pushOntoSorter(pParse, v, pOrderBy);
      }else{
        sqlite3VdbeAddOp(v, OP_MemStore, iParm, 1);
        sqlite3VdbeAddOp(v, OP_Goto, 0, iBreak);
      }
      break;
    }


    /* Send the data to the callback function.
    */
    case SRT_Callback:
    case SRT_Sorter: {
      if( pOrderBy ){
        sqlite3VdbeAddOp(v, OP_MakeRecord, nColumn, 0);
................................................................................
        pushOntoSorter(pParse, v, pOrderBy);
      }else{
        sqlite3VdbeAddOp(v, OP_Gosub, 0, iParm);
      }
      break;
    }


    /* Discard the results.  This is used for SELECT statements inside
    ** the body of a TRIGGER.  The purpose of such selects is to call
    ** user-defined functions that have side effects.  We do not care
    ** about the actual results of the select.
    */
    default: {
      assert( eDest==SRT_Discard );
      sqlite3VdbeAddOp(v, OP_Pop, nColumn, 0);
      break;
    }

  }
  return 0;
}

/*
** If the inner loop was generated using a non-null pOrderBy argument,
** then the results were placed in a sorter.  After the loop is terminated
................................................................................
    case SRT_Table:
    case SRT_TempTable: {
      sqlite3VdbeAddOp(v, OP_NewRecno, iParm, 0);
      sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
      sqlite3VdbeAddOp(v, OP_PutIntKey, iParm, 0);
      break;
    }

    case SRT_Set: {
      assert( nColumn==1 );
      sqlite3VdbeAddOp(v, OP_NotNull, -1, sqlite3VdbeCurrentAddr(v)+3);
      sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
      sqlite3VdbeAddOp(v, OP_Goto, 0, sqlite3VdbeCurrentAddr(v)+3);
      sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, "n", P3_STATIC);
      sqlite3VdbeAddOp(v, OP_String8, 0, 0);
................................................................................
    case SRT_Exists:
    case SRT_Mem: {
      assert( nColumn==1 );
      sqlite3VdbeAddOp(v, OP_MemStore, iParm, 1);
      sqlite3VdbeAddOp(v, OP_Goto, 0, end1);
      break;
    }

    case SRT_Callback:
    case SRT_Subroutine: {
      int i;
      sqlite3VdbeAddOp(v, OP_Integer, p->pEList->nExpr, 0);
      sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
      for(i=0; i<nColumn; i++){
        sqlite3VdbeAddOp(v, OP_Column, -1-i, i);
................................................................................
      if( iCol<0 ){
        zType = "INTEGER";
      }else{
        zType = pTab->aCol[iCol].zType;
      }
      break;
    }

    case TK_SELECT: {
      Select *pS = pExpr->pSelect;
      zType = columnType(pParse, pS->pSrc, pS->pEList->a[0].pExpr); 
      break;
    }

    default:
      zType = 0;
  }
  
  return zType;
}

................................................................................
      sprintf(zName, "column%d", i+1);
      sqlite3VdbeSetColName(v, i, zName, 0);
    }
  }
  generateColumnTypes(pParse, pTabList, pEList);
}


/*
** Name of the connection operator, used for error messages.
*/
static const char *selectOpName(int id){
  char *z;
  switch( id ){
    case TK_ALL:       z = "UNION ALL";   break;
    case TK_INTERSECT: z = "INTERSECT";   break;
    case TK_EXCEPT:    z = "EXCEPT";      break;
    default:           z = "UNION";       break;
  }
  return z;
}


/*
** Forward declaration
*/
static int prepSelectStmt(Parse*, Select*);

/*
................................................................................
    if( pFrom->pTab!=0 ){
      /* This statement has already been prepared.  There is no need
      ** to go further. */
      assert( i==0 );
      return 0;
    }
    if( pFrom->zName==0 ){

      /* 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 = 
................................................................................
        return 1;
      }
      /* The isTransient flag indicates that the Table structure has been
      ** dynamically allocated and may be freed at any time.  In other words,
      ** pTab is not pointing to a persistent table structure that defines
      ** part of the schema. */
      pTab->isTransient = 1;

    }else{
      /* An ordinary table or view name in the FROM clause */
      pFrom->pTab = pTab = 
        sqlite3LocateTable(pParse,pFrom->zName,pFrom->zDatabase);
      if( pTab==0 ){
        return 1;
      }

      if( pTab->pSelect ){
        /* We reach here if the named table is a really a view */
        if( sqlite3ViewGetColumnNames(pParse, pTab) ){
          return 1;
        }
        /* If pFrom->pSelect!=0 it means we are dealing with a
        ** view within a view.  The SELECT structure has already been
................................................................................
        ** copied by the outer view so we can skip the copy step here
        ** in the inner view.
        */
        if( pFrom->pSelect==0 ){
          pFrom->pSelect = sqlite3SelectDup(pTab->pSelect);
        }
      }

    }
  }

  /* Process NATURAL keywords, and ON and USING clauses of joins.
  */
  if( sqliteProcessJoin(pParse, p) ) return 1;

................................................................................
        sqlite3SelectUnbind(pItem->pSelect);
      }
    }
  }
}
#endif


/*
** This routine associates entries in an ORDER BY expression list with
** columns in a result.  For each ORDER BY expression, the opcode of
** the top-level node is changed to TK_COLUMN and the iColumn value of
** the top-level node is filled in with column number and the iTable
** value of the top-level node is filled with iTable parameter.
**
................................................................................
        "ORDER BY term number %d does not match any result column", i+1);
      nErr++;
      break;
    }
  }
  return nErr;  
}


/*
** Get a VDBE for the given parser context.  Create a new one if necessary.
** If an error occurs, return NULL and leave a message in pParse.
*/
Vdbe *sqlite3GetVdbe(Parse *pParse){
  Vdbe *v = pParse->pVdbe;
................................................................................
  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 );

  if( (eDest==SRT_Mem || eDest==SRT_Set) && pEList->nExpr>1 ){
    sqlite3ErrorMsg(pParse, "only a single result allowed for "
       "a SELECT that is part of an expression");
    goto select_end;
  }


  /* ORDER BY is ignored for some destinations.
  */
  switch( eDest ){
    case SRT_Union:
    case SRT_Except:
    case SRT_Discard:
................................................................................
  /* If there is an ORDER BY clause, then we need to sort the results
  ** and send them to the callback one by one.
  */
  if( pOrderBy ){
    generateSortTail(pParse, p, v, pEList->nExpr, eDest, iParm);
  }


  /* If this was a subquery, we have now converted the subquery into a
  ** temporary table.  So delete the subquery structure from the parent
  ** to prevent this subquery from being evaluated again and to force the
  ** the use of the temporary table.
  */
  if( pParent ){
    assert( pParent->pSrc->nSrc>parentTab );
    assert( pParent->pSrc->a[parentTab].pSelect==p );
    sqlite3SelectDelete(p);
    pParent->pSrc->a[parentTab].pSelect = 0;
  }


  /* The SELECT was successfully coded.   Set the return code to 0
  ** to indicate no errors.
  */
  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 1.233 2005/01/21 08:13:15 danielk1977 Exp $
*/
#include "sqliteInt.h"


/*
** Allocate a new Select structure and return a pointer to that
** structure.
................................................................................
        sqlite3VdbeAddOp(v, OP_NewRecno, iParm, 0);
        sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
        sqlite3VdbeAddOp(v, OP_PutIntKey, iParm, 0);
      }
      break;
    }

#ifndef SQLITE_OMIT_SUBQUERY
    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
    ** then there should be a single item on the stack.  Write this
    ** item into the set table with bogus data.
    */
    case SRT_Set: {
      int addr1 = sqlite3VdbeCurrentAddr(v);
      int addr2;
................................................................................
        pushOntoSorter(pParse, v, pOrderBy);
      }else{
        sqlite3VdbeAddOp(v, OP_MemStore, iParm, 1);
        sqlite3VdbeAddOp(v, OP_Goto, 0, iBreak);
      }
      break;
    }
#endif /* #ifndef SQLITE_OMIT_SUBQUERY */

    /* Send the data to the callback function.
    */
    case SRT_Callback:
    case SRT_Sorter: {
      if( pOrderBy ){
        sqlite3VdbeAddOp(v, OP_MakeRecord, nColumn, 0);
................................................................................
        pushOntoSorter(pParse, v, pOrderBy);
      }else{
        sqlite3VdbeAddOp(v, OP_Gosub, 0, iParm);
      }
      break;
    }

#if !defined(SQLITE_OMIT_TRIGGER) || !defined(SQLITE_OMIT_CURSOR)
    /* Discard the results.  This is used for SELECT statements inside
    ** the body of a TRIGGER.  The purpose of such selects is to call
    ** user-defined functions that have side effects.  We do not care
    ** about the actual results of the select.
    */
    default: {
      assert( eDest==SRT_Discard );
      sqlite3VdbeAddOp(v, OP_Pop, nColumn, 0);
      break;
    }
#endif
  }
  return 0;
}

/*
** If the inner loop was generated using a non-null pOrderBy argument,
** then the results were placed in a sorter.  After the loop is terminated
................................................................................
    case SRT_Table:
    case SRT_TempTable: {
      sqlite3VdbeAddOp(v, OP_NewRecno, iParm, 0);
      sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
      sqlite3VdbeAddOp(v, OP_PutIntKey, iParm, 0);
      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case SRT_Set: {
      assert( nColumn==1 );
      sqlite3VdbeAddOp(v, OP_NotNull, -1, sqlite3VdbeCurrentAddr(v)+3);
      sqlite3VdbeAddOp(v, OP_Pop, 1, 0);
      sqlite3VdbeAddOp(v, OP_Goto, 0, sqlite3VdbeCurrentAddr(v)+3);
      sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, "n", P3_STATIC);
      sqlite3VdbeAddOp(v, OP_String8, 0, 0);
................................................................................
    case SRT_Exists:
    case SRT_Mem: {
      assert( nColumn==1 );
      sqlite3VdbeAddOp(v, OP_MemStore, iParm, 1);
      sqlite3VdbeAddOp(v, OP_Goto, 0, end1);
      break;
    }
#endif
    case SRT_Callback:
    case SRT_Subroutine: {
      int i;
      sqlite3VdbeAddOp(v, OP_Integer, p->pEList->nExpr, 0);
      sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
      for(i=0; i<nColumn; i++){
        sqlite3VdbeAddOp(v, OP_Column, -1-i, i);
................................................................................
      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;
  }
  
  return zType;
}

................................................................................
      sprintf(zName, "column%d", i+1);
      sqlite3VdbeSetColName(v, i, zName, 0);
    }
  }
  generateColumnTypes(pParse, pTabList, pEList);
}

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** Name of the connection operator, used for error messages.
*/
static const char *selectOpName(int id){
  char *z;
  switch( id ){
    case TK_ALL:       z = "UNION ALL";   break;
    case TK_INTERSECT: z = "INTERSECT";   break;
    case TK_EXCEPT:    z = "EXCEPT";      break;
    default:           z = "UNION";       break;
  }
  return z;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

/*
** Forward declaration
*/
static int prepSelectStmt(Parse*, Select*);

/*
................................................................................
    if( pFrom->pTab!=0 ){
      /* This statement has already been prepared.  There is no need
      ** to go further. */
      assert( i==0 );
      return 0;
    }
    if( pFrom->zName==0 ){
#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 = 
................................................................................
        return 1;
      }
      /* The isTransient flag indicates that the Table structure has been
      ** dynamically allocated and may be freed at any time.  In other words,
      ** pTab is not pointing to a persistent table structure that defines
      ** part of the schema. */
      pTab->isTransient = 1;
#endif
    }else{
      /* An ordinary table or view name in the FROM clause */
      pFrom->pTab = pTab = 
        sqlite3LocateTable(pParse,pFrom->zName,pFrom->zDatabase);
      if( pTab==0 ){
        return 1;
      }
#ifndef SQLITE_OMIT_VIEW
      if( pTab->pSelect ){
        /* We reach here if the named table is a really a view */
        if( sqlite3ViewGetColumnNames(pParse, pTab) ){
          return 1;
        }
        /* If pFrom->pSelect!=0 it means we are dealing with a
        ** view within a view.  The SELECT structure has already been
................................................................................
        ** copied by the outer view so we can skip the copy step here
        ** in the inner view.
        */
        if( pFrom->pSelect==0 ){
          pFrom->pSelect = sqlite3SelectDup(pTab->pSelect);
        }
      }
#endif
    }
  }

  /* Process NATURAL keywords, and ON and USING clauses of joins.
  */
  if( sqliteProcessJoin(pParse, p) ) return 1;

................................................................................
        sqlite3SelectUnbind(pItem->pSelect);
      }
    }
  }
}
#endif

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** This routine associates entries in an ORDER BY expression list with
** columns in a result.  For each ORDER BY expression, the opcode of
** the top-level node is changed to TK_COLUMN and the iColumn value of
** the top-level node is filled in with column number and the iTable
** value of the top-level node is filled with iTable parameter.
**
................................................................................
        "ORDER BY term number %d does not match any result column", i+1);
      nErr++;
      break;
    }
  }
  return nErr;  
}
#endif /* #ifndef SQLITE_OMIT_COMPOUND_SELECT */

/*
** Get a VDBE for the given parser context.  Create a new one if necessary.
** If an error occurs, return NULL and leave a message in pParse.
*/
Vdbe *sqlite3GetVdbe(Parse *pParse){
  Vdbe *v = pParse->pVdbe;
................................................................................
  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 "
       "a SELECT that is part of an expression");
    goto select_end;
  }
#endif

  /* ORDER BY is ignored for some destinations.
  */
  switch( eDest ){
    case SRT_Union:
    case SRT_Except:
    case SRT_Discard:
................................................................................
  /* If there is an ORDER BY clause, then we need to sort the results
  ** and send them to the callback one by one.
  */
  if( pOrderBy ){
    generateSortTail(pParse, p, v, pEList->nExpr, eDest, iParm);
  }

#ifndef SQLITE_OMIT_SUBQUERY
  /* If this was a subquery, we have now converted the subquery into a
  ** temporary table.  So delete the subquery structure from the parent
  ** to prevent this subquery from being evaluated again and to force the
  ** the use of the temporary table.
  */
  if( pParent ){
    assert( pParent->pSrc->nSrc>parentTab );
    assert( pParent->pSrc->a[parentTab].pSelect==p );
    sqlite3SelectDelete(p);
    pParent->pSrc->a[parentTab].pSelect = 0;
  }
#endif

  /* The SELECT was successfully coded.   Set the return code to 0
  ** to indicate no errors.
  */
  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 share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the btree.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test3.c,v 1.60 2005/01/20 05:24:33 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "pager.h"
#include "btree.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
................................................................................

  if( argc!=2 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
       " ID\"", 0);
    return TCL_ERROR;
  }
  pBt = sqlite3TextToPtr(argv[1]);

  sqlite3pager_refdump(sqlite3BtreePager(pBt));

  return TCL_OK;
}

/*
** Usage:   btree_integrity_check ID ROOT ...
**
** Look through every page of the given BTree file to verify correct

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the btree.c module in SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test3.c,v 1.61 2005/01/21 08:13:15 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "pager.h"
#include "btree.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
................................................................................

  if( argc!=2 ){
    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
       " ID\"", 0);
    return TCL_ERROR;
  }
  pBt = sqlite3TextToPtr(argv[1]);
#ifdef SQLITE_DEBUG
  sqlite3pager_refdump(sqlite3BtreePager(pBt));
#endif
  return TCL_OK;
}

/*
** Usage:   btree_integrity_check ID ROOT ...
**
** Look through every page of the given BTree file to verify correct

**
** 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 1.444 2005/01/20 22:48:48 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*
................................................................................

/* Opcode: String8 * * P3
**
** P3 points to a nul terminated UTF-8 string. This opcode is transformed
** into an OP_String before it is executed for the first time.
*/
case OP_String8: {         /* same as TK_STRING */

  pOp->opcode = OP_String;

  if( db->enc!=SQLITE_UTF8 && pOp->p3 ){
    pTos++;
    sqlite3VdbeMemSetStr(pTos, pOp->p3, -1, SQLITE_UTF8, SQLITE_STATIC);
    if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pTos, db->enc) ) goto no_mem;
    if( SQLITE_OK!=sqlite3VdbeMemDynamicify(pTos) ) goto no_mem;
................................................................................
    if( pOp->p3type==P3_DYNAMIC ){
      sqliteFree(pOp->p3);
    }
    pOp->p3type = P3_DYNAMIC;
    pOp->p3 = pTos->z;
    break;
  }

  /* Otherwise fall through to the next case, OP_String */
}
  
/* Opcode: String * * P3
**
** The string value P3 is pushed onto the stack.  If P3==0 then a
** NULL is pushed onto the stack. P3 is assumed to be a nul terminated
................................................................................
    }
    pOp->p3type = P3_STATIC;
    pOp->p3 = "";
  }

  /* Fall through to the next case, OP_Blob. */
}
#endif /* SQLITE_OMIT_BLOB_LITERAL */

/* Opcode: Blob P1 * P3
**
** P3 points to a blob of data P1 bytes long. Push this
** value onto the stack. This instruction is not coded directly
** by the compiler. Instead, the compiler layer specifies
** an OP_HexBlob opcode, with the hex string representation of
** the blob as P3. This opcode is transformed to an OP_Blob
** before execution (within the sqlite3_prepare() function).
*/
case OP_Blob: {
  pTos++;
  sqlite3VdbeMemSetStr(pTos, pOp->p3, pOp->p1, 0, 0);
  break;
}


/* Opcode: Variable P1 * *
**
** Push the value of variable P1 onto the stack.  A variable is
** an unknown in the original SQL string as handed to sqlite3_compile().
** Any occurance of the '?' character in the original SQL is considered
** a variable.  Variables in the SQL string are number from left to
................................................................................
      i64 payloadSize64;
      sqlite3BtreeKeySize(pCrsr, &payloadSize64);
      payloadSize = payloadSize64;
    }else{
      sqlite3BtreeDataSize(pCrsr, &payloadSize);
    }
    nField = pC->nField;

  }else if( pC->pseudoTable ){
    /* The record is the sole entry of a pseudo-table */
    payloadSize = pC->nData;
    zRec = pC->pData;
    pC->cacheValid = 0;
    assert( payloadSize==0 || zRec!=0 );
    nField = pC->nField;
    pCrsr = 0;

  }else{
    zRec = 0;
    payloadSize = 0;
    pCrsr = 0;
    nField = 0;
  }

................................................................................
      pCx->intKey = 1;
      pCx->pIncrKey = &pCx->bogusIncrKey;
    }
  }
  break;
}


/* Opcode: OpenPseudo P1 * *
**
** Open a new cursor that points to a fake table that contains a single
** row of data.  Any attempt to write a second row of data causes the
** first row to be deleted.  All data is deleted when the cursor is
** closed.
**
................................................................................
  pCx = allocateCursor(p, i);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
  pCx->pseudoTable = 1;
  pCx->pIncrKey = &pCx->bogusIncrKey;
  break;
}


/* Opcode: Close P1 * *
**
** Close a cursor previously opened as P1.  If P1 is not
** currently open, this instruction is a no-op.
*/
case OP_Close: {
................................................................................
    }
    if( pTos->flags & MEM_Null ){
      pTos->z = 0;
      pTos->n = 0;
    }else{
      assert( pTos->flags & (MEM_Blob|MEM_Str) );
    }

    if( pC->pseudoTable ){
      /* PutStrKey does not work for pseudo-tables.
      ** The following assert makes sure we are not trying to use
      ** PutStrKey on a pseudo-table
      */
      assert( pOp->opcode==OP_PutIntKey );
      sqliteFree(pC->pData);
................................................................................
        if( !pC->pData ) goto no_mem;
        memcpy(pC->pData, pTos->z, pC->nData);
        pC->pData[pC->nData] = 0;
        pC->pData[pC->nData+1] = 0;
      }
      pC->nullRow = 0;
    }else{

      rc = sqlite3BtreeInsert(pC->pCursor, zKey, nKey, pTos->z, pTos->n);

    }


    pC->recnoIsValid = 0;
    pC->deferredMoveto = 0;
    pC->cacheValid = 0;
  }
  popStack(&pTos, 2);
  break;
}
................................................................................
      pTos->z = z;
    }
    if( pC->keyAsData || pOp->opcode==OP_RowKey ){
      sqlite3BtreeKey(pCrsr, 0, n, pTos->z);
    }else{
      sqlite3BtreeData(pCrsr, 0, n, pTos->z);
    }

  }else if( pC->pseudoTable ){
    pTos->n = pC->nData;
    pTos->z = pC->pData;
    pTos->flags = MEM_Blob|MEM_Ephem;

  }else{
    pTos->flags = MEM_Null;
  }
  break;
}

/* Opcode: Recno P1 * *
................................................................................
    v = keyToInt(v);
  }
  pTos->i = v;
  pTos->flags = MEM_Int;
  break;
}


/* Opcode: FullKey P1 * *
**
** Extract the complete key from the record that cursor P1 is currently
** pointing to and push the key onto the stack as a string.
**
** Compare this opcode to Recno.  The Recno opcode extracts the first
** 4 bytes of the key and pushes those bytes onto the stack as an
................................................................................
    }
    sqlite3BtreeKey(pCrsr, 0, amt, z);
    pTos->z = z;
    pTos->n = amt;
  }
  break;
}


/* Opcode: NullRow P1 * *
**
** Move the cursor P1 to a null row.  Any OP_Column operations
** that occur while the cursor is on the null row will always push 
** a NULL onto the stack.
*/
................................................................................
  if( p->pList ){
    sqlite3VdbeKeylistFree(p->pList);
    p->pList = 0;
  }
  break;
}


/* 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.
*/
case OP_ContextPush: {
................................................................................
  assert( p->contextStackTop>=0 );
  db->lastRowid = pContext->lastRowid;
  p->nChange = pContext->nChange;
  sqlite3VdbeKeylistFree(p->pList);
  p->pList = pContext->pList;
  break;
}


/* Opcode: SortPut * * *
**
** The TOS is the key and the NOS is the data.  Pop both from the stack
** and put them on the sorter.  The key and data should have been
** made using the MakeRecord opcode.
*/

**
** 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 1.445 2005/01/21 08:13:15 danielk1977 Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*
................................................................................

/* Opcode: String8 * * P3
**
** P3 points to a nul terminated UTF-8 string. This opcode is transformed
** into an OP_String before it is executed for the first time.
*/
case OP_String8: {         /* same as TK_STRING */
#ifndef SQLITE_OMIT_UTF16
  pOp->opcode = OP_String;

  if( db->enc!=SQLITE_UTF8 && pOp->p3 ){
    pTos++;
    sqlite3VdbeMemSetStr(pTos, pOp->p3, -1, SQLITE_UTF8, SQLITE_STATIC);
    if( SQLITE_OK!=sqlite3VdbeChangeEncoding(pTos, db->enc) ) goto no_mem;
    if( SQLITE_OK!=sqlite3VdbeMemDynamicify(pTos) ) goto no_mem;
................................................................................
    if( pOp->p3type==P3_DYNAMIC ){
      sqliteFree(pOp->p3);
    }
    pOp->p3type = P3_DYNAMIC;
    pOp->p3 = pTos->z;
    break;
  }
#endif
  /* Otherwise fall through to the next case, OP_String */
}
  
/* Opcode: String * * P3
**
** The string value P3 is pushed onto the stack.  If P3==0 then a
** NULL is pushed onto the stack. P3 is assumed to be a nul terminated
................................................................................
    }
    pOp->p3type = P3_STATIC;
    pOp->p3 = "";
  }

  /* Fall through to the next case, OP_Blob. */
}


/* Opcode: Blob P1 * P3
**
** P3 points to a blob of data P1 bytes long. Push this
** value onto the stack. This instruction is not coded directly
** by the compiler. Instead, the compiler layer specifies
** an OP_HexBlob opcode, with the hex string representation of
** the blob as P3. This opcode is transformed to an OP_Blob
** the first time it is executed.
*/
case OP_Blob: {
  pTos++;
  sqlite3VdbeMemSetStr(pTos, pOp->p3, pOp->p1, 0, 0);
  break;
}
#endif /* SQLITE_OMIT_BLOB_LITERAL */

/* Opcode: Variable P1 * *
**
** Push the value of variable P1 onto the stack.  A variable is
** an unknown in the original SQL string as handed to sqlite3_compile().
** Any occurance of the '?' character in the original SQL is considered
** a variable.  Variables in the SQL string are number from left to
................................................................................
      i64 payloadSize64;
      sqlite3BtreeKeySize(pCrsr, &payloadSize64);
      payloadSize = payloadSize64;
    }else{
      sqlite3BtreeDataSize(pCrsr, &payloadSize);
    }
    nField = pC->nField;
#ifndef SQLITE_OMIT_TRIGGER
  }else if( pC->pseudoTable ){
    /* The record is the sole entry of a pseudo-table */
    payloadSize = pC->nData;
    zRec = pC->pData;
    pC->cacheValid = 0;
    assert( payloadSize==0 || zRec!=0 );
    nField = pC->nField;
    pCrsr = 0;
#endif
  }else{
    zRec = 0;
    payloadSize = 0;
    pCrsr = 0;
    nField = 0;
  }

................................................................................
      pCx->intKey = 1;
      pCx->pIncrKey = &pCx->bogusIncrKey;
    }
  }
  break;
}

#ifndef SQLITE_OMIT_TRIGGER
/* Opcode: OpenPseudo P1 * *
**
** Open a new cursor that points to a fake table that contains a single
** row of data.  Any attempt to write a second row of data causes the
** first row to be deleted.  All data is deleted when the cursor is
** closed.
**
................................................................................
  pCx = allocateCursor(p, i);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
  pCx->pseudoTable = 1;
  pCx->pIncrKey = &pCx->bogusIncrKey;
  break;
}
#endif

/* Opcode: Close P1 * *
**
** Close a cursor previously opened as P1.  If P1 is not
** currently open, this instruction is a no-op.
*/
case OP_Close: {
................................................................................
    }
    if( pTos->flags & MEM_Null ){
      pTos->z = 0;
      pTos->n = 0;
    }else{
      assert( pTos->flags & (MEM_Blob|MEM_Str) );
    }
#ifndef SQLITE_OMIT_TRIGGER
    if( pC->pseudoTable ){
      /* PutStrKey does not work for pseudo-tables.
      ** The following assert makes sure we are not trying to use
      ** PutStrKey on a pseudo-table
      */
      assert( pOp->opcode==OP_PutIntKey );
      sqliteFree(pC->pData);
................................................................................
        if( !pC->pData ) goto no_mem;
        memcpy(pC->pData, pTos->z, pC->nData);
        pC->pData[pC->nData] = 0;
        pC->pData[pC->nData+1] = 0;
      }
      pC->nullRow = 0;
    }else{
#endif
      rc = sqlite3BtreeInsert(pC->pCursor, zKey, nKey, pTos->z, pTos->n);
#ifndef SQLITE_OMIT_TRIGGER
    }
#endif
    
    pC->recnoIsValid = 0;
    pC->deferredMoveto = 0;
    pC->cacheValid = 0;
  }
  popStack(&pTos, 2);
  break;
}
................................................................................
      pTos->z = z;
    }
    if( pC->keyAsData || pOp->opcode==OP_RowKey ){
      sqlite3BtreeKey(pCrsr, 0, n, pTos->z);
    }else{
      sqlite3BtreeData(pCrsr, 0, n, pTos->z);
    }
#ifndef SQLITE_OMIT_TRIGGER
  }else if( pC->pseudoTable ){
    pTos->n = pC->nData;
    pTos->z = pC->pData;
    pTos->flags = MEM_Blob|MEM_Ephem;
#endif
  }else{
    pTos->flags = MEM_Null;
  }
  break;
}

/* Opcode: Recno P1 * *
................................................................................
    v = keyToInt(v);
  }
  pTos->i = v;
  pTos->flags = MEM_Int;
  break;
}

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/* Opcode: FullKey P1 * *
**
** Extract the complete key from the record that cursor P1 is currently
** pointing to and push the key onto the stack as a string.
**
** Compare this opcode to Recno.  The Recno opcode extracts the first
** 4 bytes of the key and pushes those bytes onto the stack as an
................................................................................
    }
    sqlite3BtreeKey(pCrsr, 0, amt, z);
    pTos->z = z;
    pTos->n = amt;
  }
  break;
}
#endif

/* Opcode: NullRow P1 * *
**
** Move the cursor P1 to a null row.  Any OP_Column operations
** that occur while the cursor is on the null row will always push 
** a NULL onto the stack.
*/
................................................................................
  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.
*/
case OP_ContextPush: {
................................................................................
  assert( p->contextStackTop>=0 );
  db->lastRowid = pContext->lastRowid;
  p->nChange = pContext->nChange;
  sqlite3VdbeKeylistFree(p->pList);
  p->pList = pContext->pList;
  break;
}
#endif /* #ifndef SQLITE_OMIT_TRIGGER */

/* Opcode: SortPut * * *
**
** The TOS is the key and the NOS is the data.  Pop both from the stack
** and put them on the sorter.  The key and data should have been
** made using the MakeRecord opcode.
*/

#
# Run this Tcl script to generate the compile.html file.
#
set rcsid {$Id: compile.tcl,v 1.2 2004/11/20 08:17:18 danielk1977 Exp $ }
source common.tcl
header {Compilation Options For SQLite}

puts {
<h1>Compilation Options For SQLite</h1>

<p>
................................................................................

<p><b>SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS</b><br>
Defining this option omits pragmas for querying and modifying the 
database schema version and user version from the build. Specifically, the 
<a href="pragma.html#pragma_schema_version">schema_version</a> and
<a href="pragma.html#pragma_user_version">user_version</a>
pragmas are omitted.





<p><b>SQLITE_OMIT_TCL_VARIABLE</b><br>
<p>If this macro is defined, then the special "$<variable-name>" syntax
used to automatically bind SQL variables to TCL variables is omitted.
</p>

<p><b>SQLITE_OMIT_TRIGGER</b><br>

#
# Run this Tcl script to generate the compile.html file.
#
set rcsid {$Id: compile.tcl,v 1.3 2005/01/21 08:13:15 danielk1977 Exp $ }
source common.tcl
header {Compilation Options For SQLite}

puts {
<h1>Compilation Options For SQLite</h1>

<p>
................................................................................

<p><b>SQLITE_OMIT_SCHEMA_VERSION_PRAGMAS</b><br>
Defining this option omits pragmas for querying and modifying the 
database schema version and user version from the build. Specifically, the 
<a href="pragma.html#pragma_schema_version">schema_version</a> and
<a href="pragma.html#pragma_user_version">user_version</a>
pragmas are omitted.

<p><b>SQLITE_OMIT_SUBQUERY</b><br>
<p>If defined, support for sub-selects and the IN() operator are omitted.
</p>

<p><b>SQLITE_OMIT_TCL_VARIABLE</b><br>
<p>If this macro is defined, then the special "$<variable-name>" syntax
used to automatically bind SQL variables to TCL variables is omitted.
</p>

<p><b>SQLITE_OMIT_TRIGGER</b><br>