SQLite

**    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 1.110 2005/09/08 01:58:43 drh 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.

  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    goto delete_from_cleanup;
  }
  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
  sqlite3BeginWriteOperation(pParse, triggers_exist, pTab->iDb);

  /* If we are trying to delete from a view, realize that view into
  ** a ephemeral table.
  */
  if( isView ){
    Select *pView = sqlite3SelectDup(pTab->pSelect);
    sqlite3Select(pParse, pView, SRT_VirtualTab, 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 C code routines that are called by the parser
** to handle SELECT statements in SQLite.
**
** $Id: select.c,v 1.265 2005/09/08 01:58:43 drh Exp $
*/
#include "sqliteInt.h"


/*
** Allocate a new Select structure and return a pointer to that
** structure.

/*
** 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){
  sqlite3ExprCodeExprList(pParse, pOrderBy);
  sqlite3VdbeAddOp(v, OP_Sequence, pOrderBy->iECursor, 0);
  sqlite3VdbeAddOp(v, OP_Pull, pOrderBy->nExpr + 1, 0);
  sqlite3VdbeAddOp(v, OP_MakeRecord, pOrderBy->nExpr + 2, 0);
  sqlite3VdbeAddOp(v, OP_IdxInsert, pOrderBy->iECursor, 0);
}

/*
** Add code to implement the OFFSET and LIMIT
*/
static void codeLimiter(
  Vdbe *v,          /* Generate code into this VM */

      break;
    }
#endif

    /* Store the result as data using a unique key.
    */
    case SRT_Table:
    case SRT_VirtualTab: {
      sqlite3VdbeAddOp(v, OP_MakeRecord, nColumn, 0);
      if( pOrderBy ){
        pushOntoSorter(pParse, v, pOrderBy);
      }else{
        sqlite3VdbeAddOp(v, OP_NewRowid, iParm, 0);
        sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
        sqlite3VdbeAddOp(v, OP_Insert, iParm, 0);

#endif /* #ifndef SQLITE_OMIT_SUBQUERY */

    /* Send the data to the callback function or to a subroutine.  In the
    ** case of a subroutine, the subroutine itself is responsible for
    ** popping the data from the stack.
    */
    case SRT_Subroutine:
    case SRT_Callback: {

      if( pOrderBy ){
        sqlite3VdbeAddOp(v, OP_MakeRecord, nColumn, 0);
        pushOntoSorter(pParse, v, pOrderBy);
      }else if( eDest==SRT_Subroutine ){
        sqlite3VdbeAddOp(v, OP_Gosub, 0, iParm);
      }else{

        sqlite3VdbeAddOp(v, OP_Callback, nColumn, 0);
      }
      break;
    }

#if !defined(SQLITE_OMIT_TRIGGER)
    /* Discard the results.  This is used for SELECT statements inside

){
  int brk = sqlite3VdbeMakeLabel(v);
  int cont = sqlite3VdbeMakeLabel(v);
  int addr;
  int iTab;
  ExprList *pOrderBy = p->pOrderBy;


  iTab = pOrderBy->iECursor;
  addr = 1 + sqlite3VdbeAddOp(v, OP_Sort, iTab, brk);
  codeLimiter(v, p, cont, brk, 0);
  sqlite3VdbeAddOp(v, OP_Column, iTab, pOrderBy->nExpr + 1);
  switch( eDest ){
    case SRT_Table:
    case SRT_VirtualTab: {
      sqlite3VdbeAddOp(v, OP_NewRowid, iParm, 0);
      sqlite3VdbeAddOp(v, OP_Pull, 1, 0);
      sqlite3VdbeAddOp(v, OP_Insert, iParm, 0);
      break;
    }
#ifndef SQLITE_OMIT_SUBQUERY
    case SRT_Set: {

/*
** Allocate a virtual index to use for sorting.
*/
static void createSortingIndex(Parse *pParse, Select *p, ExprList *pOrderBy){
  if( pOrderBy ){
    int addr;
    assert( pOrderBy->iECursor==0 );
    pOrderBy->iECursor = pParse->nTab++;
    addr = sqlite3VdbeAddOp(pParse->pVdbe, OP_OpenVirtual,
                            pOrderBy->iECursor, pOrderBy->nExpr+1);
    assert( p->addrOpenVirt[2] == -1 );
    p->addrOpenVirt[2] = addr;
  }
}

/*
** The opcode at addr is an OP_OpenVirtual that created a sorting

  if( v==0 ){
    rc = 1;
    goto multi_select_end;
  }

  /* Create the destination temporary table if necessary
  */
  if( eDest==SRT_VirtualTab ){
    assert( p->pEList );
    assert( nSetP2<sizeof(aSetP2)/sizeof(aSetP2[0]) );
    aSetP2[nSetP2++] = sqlite3VdbeAddOp(v, OP_OpenVirtual, iParm, 0);
    eDest = SRT_Table;
  }

  /* Generate code for the left and right SELECT statements.

  ** The column names have already been generated in the calling function.
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ) return 0;

  /* If the output is destined for a temporary table, open that table.
  */
  if( eDest==SRT_VirtualTab ){
    sqlite3VdbeAddOp(v, OP_OpenVirtual, iParm, 1);
  }

  /* Generating code to find the min or the max.  Basically all we have
  ** to do is find the first or the last entry in the chosen index.  If
  ** the min() or max() is on the INTEGER PRIMARY KEY, then find the first
  ** or last entry in the main table.

  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 */
  int addrSortIndex;     /* Address of an OP_OpenVirtual instruction */
  AggInfo sAggInfo;      /* Information used by aggregate queries */

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

#ifndef SQLITE_OMIT_COMPOUND_SELECT

    if( pItem->zName!=0 ){
      zSavedAuthContext = pParse->zAuthContext;
      pParse->zAuthContext = pItem->zName;
      needRestoreContext = 1;
    }else{
      needRestoreContext = 0;
    }
    sqlite3Select(pParse, pItem->pSelect, SRT_VirtualTab, 
                 pItem->iCursor, p, i, &isAgg, 0);
    if( needRestoreContext ){
      pParse->zAuthContext = zSavedAuthContext;
    }
    pTabList = p->pSrc;
    pWhere = p->pWhere;
    if( !IgnorableOrderby(eDest) ){

      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 and create a sorting index.
  **
  ** This sorting index might end up being unused if the data can be 
  ** extracted in pre-sorted order.  If that is the case, then the
  ** OP_OpenVirtual instruction will be changed to an OP_Noop once
  ** we figure out that the sorting index is not needed.  The addrSortIndex
  ** variable is used to facilitate that change.
  */
  if( pOrderBy ){
    struct ExprList_item *pTerm;
    KeyInfo *pKeyInfo;

    for(i=0, pTerm=pOrderBy->a; i<pOrderBy->nExpr; i++, pTerm++){
      if( pTerm->zName ){
        pTerm->pExpr->pColl = sqlite3LocateCollSeq(pParse, pTerm->zName, -1);
      }
    }
    if( pParse->nErr ){
      goto select_end;
    }
    pKeyInfo = keyInfoFromExprList(pParse, pOrderBy);
    pOrderBy->iECursor = pParse->nTab++;
    p->addrOpenVirt[2] = addrSortIndex =
       sqlite3VdbeOp3(v, OP_OpenVirtual, pOrderBy->iECursor, pOrderBy->nExpr+2, 
                        (char*)pKeyInfo, P3_KEYINFO_HANDOFF);
  }else{
    addrSortIndex = -1;
  }

  /* Set the limiter.
  */
  computeLimitRegisters(pParse, p);

  /* If the output is destined for a temporary table, open that table.
  */
  if( eDest==SRT_VirtualTab ){
    sqlite3VdbeAddOp(v, OP_OpenVirtual, iParm, pEList->nExpr);
  }


  /* Initialize the memory cell to NULL for SRT_Mem or 0 for SRT_Exists
  */
  if( eDest==SRT_Mem || eDest==SRT_Exists ){

  /* Aggregate and non-aggregate queries are handled differently */
  if( !isAgg && pGroupBy==0 ){
    /* This case is for non-aggregate queries
    ** Begin the database scan
    */
    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, &pOrderBy);
    if( pWInfo==0 ) goto select_end;

    /* If sorting index that was created by a prior OP_OpenVirtual 
    ** instruction ended up not being needed, then change the OP_OpenVirtual
    ** into an OP_Noop.
    */
    if( addrSortIndex>=0 && pOrderBy==0 ){
      uncreateSortingIndex(pParse, addrSortIndex);
      p->addrOpenVirt[2] = -1;
    }

    /* Use the standard inner loop
    */
    if( selectInnerLoop(pParse, p, pEList, 0, 0, pOrderBy, distinct, eDest,
                    iParm, pWInfo->iContinue, pWInfo->iBreak, aff) ){
       goto select_end;
    }

    ** SELECT statement.
    */
    memset(&sNC, 0, sizeof(sNC));
    sNC.pParse = pParse;
    sNC.pSrcList = pTabList;
    sNC.pAggInfo = &sAggInfo;
    sAggInfo.nSortingColumn = pGroupBy ? pGroupBy->nExpr+1 : 0;
    sAggInfo.pGroupBy = pGroupBy;
    if( sqlite3ExprAnalyzeAggList(&sNC, pEList) ){
      goto select_end;
    }
    if( sqlite3ExprAnalyzeAggList(&sNC, pOrderBy) ){
      goto select_end;
    }
    if( pHaving && sqlite3ExprAnalyzeAggregates(&sNC, pHaving) ){

/*
** 2001 September 15
**
** The author disclaims copyright to this source code.  In place of
** 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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.410 2005/09/08 01:58:43 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** These #defines should enable >2GB file support on Posix if the
** underlying operating system supports it.  If the OS lacks

** list of "ID = expr" items in an UPDATE.  A list of expressions can
** also be used as the argument to a function, in which case the a.zName
** field is not used.
*/
struct ExprList {
  int nExpr;             /* Number of expressions on the list */
  int nAlloc;            /* Number of entries allocated below */
  int iECursor;          /* VDBE Cursor associated with this ExprList */
  struct ExprList_item {
    Expr *pExpr;           /* The list of expressions */
    char *zName;           /* Token associated with this expression */
    u8 sortOrder;          /* 1 for DESC or 0 for ASC */
    u8 isAgg;              /* True if this is an aggregate like count(*) */
    u8 done;               /* A flag to indicate when processing is finished */
  } *a;                  /* One entry for each expression */

/* The ORDER BY clause is ignored for all of the above */
#define IgnorableOrderby(X) (X<=SRT_Discard)

#define SRT_Callback     4  /* Invoke a callback with each row of result */
#define SRT_Mem          5  /* Store result in a memory cell */
#define SRT_Set          6  /* Store non-null results as keys in an index */
#define SRT_Table        7  /* Store result as data and add automatic rowid */
#define SRT_VirtualTab   8  /* Create virtual table and store results there */

#define SRT_Subroutine   9  /* Call a subroutine to handle results */
#define SRT_Exists      10  /* Put 0 or 1 in a memory cell */

/*
** An SQL parser context.  A copy of this structure is passed through
** the parser and down into all the parser action routine in order to
** carry around information that is global to the entire parse.
**
** The structure is divided into two parts.  When the parser and code

**    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 1.111 2005/09/08 01:58:43 drh Exp $
*/
#include "sqliteInt.h"

/*
** The most recently coded instruction was an OP_Column to retrieve column
** 'i' of table pTab. This routine sets the P3 parameter of the 
** OP_Column to the default value, if any.

  /* Begin generating code.
  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ) goto update_cleanup;
  if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
  sqlite3BeginWriteOperation(pParse, 1, pTab->iDb);

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

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

# 2001 September 15
#
# The author disclaims copyright to this source code.  In place of
# 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.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is page cache subsystem.
#
# $Id: collate3.test,v 1.11 2005/09/08 01:58:43 drh Exp $

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

#
# Tests are organised as follows:
#

  } {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 {
btree_breakpoint
    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;

#
#***********************************************************************
# 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 1.19 2005/09/08 01:58:43 drh 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 Table2 VALUES(1, 'z');
    INSERT INTO Table2 VALUES (1, 'a');
    SELECT ID, Value FROM Table1
       UNION SELECT ID, max(Value) FROM Table2 GROUP BY 1
    ORDER BY 1, 2;
  }
} {1 x 1 z}
do_test misc4-3.2 {
  catchsql { 
    SELECT ID, Value FROM Table1
       UNION SELECT ID, max(Value) FROM Table2 GROUP BY 1, 2
    ORDER BY 1, 2;
  }
} {1 {aggregate functions are not allowed in the GROUP BY clause}}
} ;# ifcapable compound

# Ticket #1047.  Make sure column types are preserved in subqueries.
#
ifcapable subquery {
  do_test misc4-4.1 {
    execsql {