SQLite

**    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 1.209 2005/06/30 17:04:21 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Return the 'affinity' of the expression pExpr if any.
**

  pNew->pOrderBy = sqlite3ExprListDup(p->pOrderBy);
  pNew->op = p->op;
  pNew->pPrior = sqlite3SelectDup(p->pPrior);
  pNew->pLimit = sqlite3ExprDup(p->pLimit);
  pNew->pOffset = sqlite3ExprDup(p->pOffset);
  pNew->iLimit = -1;
  pNew->iOffset = -1;
  pNew->ppOpenTemp = 0;
  pNew->isResolved = p->isResolved;
  pNew->isAgg = p->isAgg;
  return pNew;
}
#else
Select *sqlite3SelectDup(Select *p){
  assert( p==0 );

    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>.
      **
      ** If the 'x' expression is a column value, or the SELECT...
      ** statement returns a column value, then the affinity of that
      ** column is used to build the index keys. If both 'x' and the
      ** SELECT... statement are columns, then numeric affinity is used
      ** if either column has NUMERIC or INTEGER affinity. If neither
      ** 'x' nor the SELECT... statement are columns, then numeric affinity
      ** is used.
      */
      pExpr->iTable = pParse->nTab++;
      addr = sqlite3VdbeAddOp(v, OP_OpenTemp, pExpr->iTable, 0);
      memset(&keyInfo, 0, sizeof(keyInfo));
      keyInfo.nField = 1;
      sqlite3VdbeAddOp(v, OP_SetNumColumns, pExpr->iTable, 1);

      if( pExpr->pSelect ){
        /* Case 1:     expr IN (SELECT ...)
        **

**    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 1.140 2005/06/24 03:53:06 drh 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:

      sqlite3VdbeAddOp(v, OP_Return, 0, 0);

      /* The following code runs first because the GOTO at the very top
      ** of the program jumps to it.  Create the temporary table, then jump
      ** back up and execute the SELECT code above.
      */
      sqlite3VdbeChangeP2(v, iInitCode, sqlite3VdbeCurrentAddr(v));
      sqlite3VdbeAddOp(v, OP_OpenTemp, srcTab, 0);
      sqlite3VdbeAddOp(v, OP_SetNumColumns, srcTab, nColumn);
      sqlite3VdbeAddOp(v, OP_Goto, 0, iSelectLoop);
      sqlite3VdbeResolveLabel(v, iCleanup);
    }else{
      sqlite3VdbeChangeP2(v, iInitCode, sqlite3VdbeCurrentAddr(v));
    }
  }else{

**    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 1.252 2005/06/12 21:35:52 drh Exp $
*/
#include "sqliteInt.h"


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

** KeyInfo structure.  The number of columns in the KeyInfo is determined
** by the result set of the SELECT statement in the second argument.
**
** Specifically, this routine is called to open an index table for
** DISTINCT, UNION, INTERSECT and EXCEPT select statements (but not 
** UNION ALL).
**
** The value returned is the address of the OP_OpenTemp instruction.
*/
static int openTempIndex(Parse *pParse, Select *p, int iTab){
  KeyInfo *pKeyInfo;
  int nColumn;
  sqlite3 *db = pParse->db;
  int i;
  Vdbe *v = pParse->pVdbe;
  int addr;

  pKeyInfo->nField = nColumn;
  for(i=0; i<nColumn; i++){
    pKeyInfo->aColl[i] = sqlite3ExprCollSeq(pParse, p->pEList->a[i].pExpr);
    if( !pKeyInfo->aColl[i] ){
      pKeyInfo->aColl[i] = db->pDfltColl;
    }
  }
  addr = sqlite3VdbeOp3(v, OP_OpenTemp, iTab, 0, 
      (char*)pKeyInfo, P3_KEYINFO_HANDOFF);
  return addr;
}

#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** Add the address "addr" to the set of all OpenTemp opcode addresses
** that are being accumulated in p->ppOpenTemp.
*/
static int multiSelectOpenTempAddr(Select *p, int addr){
  IdList *pList = *p->ppOpenTemp = sqlite3IdListAppend(*p->ppOpenTemp, 0);
  if( pList==0 ){
    return SQLITE_NOMEM;
  }
  pList->a[pList->nId-1].idx = addr;
  return SQLITE_OK;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

  int eDest,            /* \___  Store query results as specified */
  int iParm,            /* /     by these two parameters.         */
  char *aff             /* If eDest is SRT_Union, the affinity string */
){
  int rc = SQLITE_OK;   /* Success code from a subroutine */
  Select *pPrior;       /* Another SELECT immediately to our left */
  Vdbe *v;              /* Generate code to this VDBE */
  IdList *pOpenTemp = 0;/* OP_OpenTemp opcodes that need a KeyInfo */
  int aAddr[5];         /* Addresses of SetNumColumns operators */
  int nAddr = 0;        /* Number used */
  int nCol;             /* Number of columns in the result set */

  /* Make sure there is no ORDER BY or LIMIT clause on prior SELECTs.  Only
  ** the last (right-most) SELECT in the series may have an ORDER BY or LIMIT.
  */

  v = sqlite3GetVdbe(pParse);
  if( v==0 ){
    rc = 1;
    goto multi_select_end;
  }

  /* If *p this is the right-most select statement, then initialize
  ** p->ppOpenTemp to point to pOpenTemp.  If *p is not the right most
  ** statement then p->ppOpenTemp will have already been initialized
  ** by a prior call to this same procedure.  Pass along the pOpenTemp
  ** pointer to pPrior, the next statement to our left.
  */
  if( p->ppOpenTemp==0 ){
    p->ppOpenTemp = &pOpenTemp;
  }
  pPrior->ppOpenTemp = p->ppOpenTemp;

  /* Create the destination temporary table if necessary
  */
  if( eDest==SRT_TempTable ){
    assert( p->pEList );
    sqlite3VdbeAddOp(v, OP_OpenTemp, iParm, 0);
    assert( nAddr==0 );
    aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, iParm, 0);
    eDest = SRT_Table;
  }

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

        */
        unionTab = pParse->nTab++;
        if( p->pOrderBy 
        && matchOrderbyToColumn(pParse, p, p->pOrderBy, unionTab, 1) ){
          rc = 1;
          goto multi_select_end;
        }
        addr = sqlite3VdbeAddOp(v, OP_OpenTemp, unionTab, 0);
        if( p->op!=TK_ALL ){
          rc = multiSelectOpenTempAddr(p, addr);
          if( rc!=SQLITE_OK ){
            goto multi_select_end;
          }
        }
	assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
        aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, unionTab, 0);
        assert( p->pEList );

      tab1 = pParse->nTab++;
      tab2 = pParse->nTab++;
      if( p->pOrderBy && matchOrderbyToColumn(pParse,p,p->pOrderBy,tab1,1) ){
        rc = 1;
        goto multi_select_end;
      }

      addr = sqlite3VdbeAddOp(v, OP_OpenTemp, tab1, 0);
      rc = multiSelectOpenTempAddr(p, addr);
      if( rc!=SQLITE_OK ){
        goto multi_select_end;
      }
      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);
      rc = multiSelectOpenTempAddr(p, addr);
      if( rc!=SQLITE_OK ){
        goto multi_select_end;
      }
      assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
      aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, tab2, 0);
      p->pPrior = 0;
      pLimit = p->pLimit;

  ** ORDER BY processing if there is an ORDER BY clause.
  **
  ** This section is run by the right-most SELECT statement only.
  ** SELECT statements to the left always skip this part.  The right-most
  ** SELECT might also skip this part if it has no ORDER BY clause and
  ** no temp tables are required.
  */
  if( p->pOrderBy || (pOpenTemp && pOpenTemp->nId>0) ){
    int i;                        /* Loop counter */
    KeyInfo *pKeyInfo;            /* Collating sequence for the result set */

    assert( p->ppOpenTemp == &pOpenTemp );
    pKeyInfo = sqliteMalloc(sizeof(*pKeyInfo)+nCol*sizeof(CollSeq*));
    if( !pKeyInfo ){
      rc = SQLITE_NOMEM;
      goto multi_select_end;
    }

    pKeyInfo->enc = pParse->db->enc;
    pKeyInfo->nField = nCol;

    for(i=0; i<nCol; i++){
      pKeyInfo->aColl[i] = multiSelectCollSeq(pParse, p, i);
      if( !pKeyInfo->aColl[i] ){
        pKeyInfo->aColl[i] = pParse->db->pDfltColl;
      }
    }

    for(i=0; pOpenTemp && i<pOpenTemp->nId; i++){
      int p3type = (i==0?P3_KEYINFO_HANDOFF:P3_KEYINFO);
      int addr = pOpenTemp->a[i].idx;
      sqlite3VdbeChangeP3(v, addr, (char *)pKeyInfo, p3type);
    }

    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);
    }

    if( !pOpenTemp ){
      /* This happens for UNION ALL ... ORDER BY */
      sqliteFree(pKeyInfo);
    }
  }

multi_select_end:
  if( pOpenTemp ){
    sqlite3IdListDelete(pOpenTemp);
  }
  p->ppOpenTemp = 0;
  return rc;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

#ifndef SQLITE_OMIT_VIEW
/*
** Scan through the expression pExpr.  Replace every reference to

  */
  v = sqlite3GetVdbe(pParse);
  if( v==0 ) return 0;

  /* If the output is destined for a temporary table, open that table.
  */
  if( eDest==SRT_TempTable ){
    sqlite3VdbeAddOp(v, OP_OpenTemp, iParm, 0);
    sqlite3VdbeAddOp(v, OP_SetNumColumns, 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.

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

  /* If the output is destined for a temporary table, open that table.
  */
  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 ){
    NameContext sNC;

    sqlite3VdbeAddOp(v, OP_MemStore, iParm, 1);
  }

  /* Open a temporary table to use for the distinct set.
  */
  if( isDistinct ){
    distinct = pParse->nTab++;
    openTempIndex(pParse, p, distinct);
  }else{
    distinct = -1;
  }

  /* Begin the database scan
  */
  pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere,

/*
** 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 1.391 2005/07/08 14:14:23 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

  ExprList *pGroupBy;    /* The GROUP BY clause */
  Expr *pHaving;         /* The HAVING clause */
  ExprList *pOrderBy;    /* The ORDER BY clause */
  Select *pPrior;        /* Prior select in a compound select statement */
  Expr *pLimit;          /* LIMIT expression. NULL means not used. */
  Expr *pOffset;         /* OFFSET expression. NULL means not used. */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
  IdList **ppOpenTemp;   /* OP_OpenTemp addresses used by multi-selects */
  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.
*/

**
** 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 1.473 2005/07/08 13:08:00 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*

    default: {
      goto abort_due_to_error;
    }
  }
  break;
}

/* Opcode: OpenTemp P1 * P3
**
** Open a new cursor to a transient table.
** The transient cursor is always opened read/write even if 
** the main database is read-only.  The transient table is deleted
** automatically when the cursor is closed.
**
** The cursor points to a BTree table if P3==0 and to a BTree index
** if P3 is not 0.  If P3 is not NULL, it points to a KeyInfo structure
** that defines the format of keys in the index.
**
** This opcode is used for tables that exist for the duration of a single
** SQL statement only.  Tables created using CREATE TEMPORARY TABLE
** are opened using OP_OpenRead or OP_OpenWrite.  "Temporary" in the
** context of this opcode means for the duration of a single SQL statement
** whereas "Temporary" in the context of CREATE TABLE means for the duration
** of the connection to the database.  Same word; different meanings.
*/
case OP_OpenTemp: {       /* no-push */
  int i = pOp->p1;
  Cursor *pCx;
  assert( i>=0 );
  pCx = allocateCursor(p, i);
  if( pCx==0 ) goto no_mem;
  pCx->nullRow = 1;
  rc = sqlite3BtreeFactory(db, 0, 1, TEMP_PAGES, &pCx->pBt);

** 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 1.141 2005/07/08 14:14:23 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.

    pLevel->inP1 = iTab;
#endif
  }
  disableTerm(pLevel, &pTerm->p);
}

/*
** The number of bits in a Bitmask
*/
#define BMS  (sizeof(Bitmask)*8-1)


/*
** Generate the beginning of the loop used for WHERE clause processing.
** The return value is a pointer to an opaque structure that contains

# 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 file is testing the INSERT statement.
#
# $Id: insert.test,v 1.26 2005/05/29 14:23:13 danielk1977 Exp $

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

# Try to insert into a non-existant table.
#
do_test insert-1.1 {

  } {1 2}
  ifcapable {explain} {
    do_test insert-5.3 {
      # verify that a temporary table is used to copy t4 to t4
      set x [execsql {
        EXPLAIN INSERT INTO t4 SELECT x+2 FROM t4;
      }]
      expr {[lsearch $x OpenTemp]>0}
    } {1}
  }
  
  do_test insert-5.4 {
    # Verify that table "test1" begins on page 3.  This should be the same
    # page number used by "t4" above.
    #

#    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

# The following procedure compiles the SQL given as an argument and returns
# TRUE if that SQL uses any transient tables and returns FALSE if no
# transient tables are used.  This is used to make sure that the
# sqliteFlattenSubquery() routine in select.c is doing its job.
#
proc is_flat {sql} {
  return [expr 0>[lsearch [execsql "EXPLAIN $sql"] OpenTemp]]
}

# Check that the flattener works correctly for deeply nested subqueries
# involving joins.
#
do_test select6-8.1 {
  execsql {

# 2002 February 26
#
# 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 file is testing VIEW statements.
#
# $Id: view.test,v 1.25 2005/06/06 15:32:08 drh 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

# This will only work if EXPLAIN is enabled.
# Ticket #272
#
ifcapable {explain} {
do_test view-5.3 {
  lsearch [execsql {
    EXPLAIN SELECT * FROM v5;
  }] OpenTemp
} {-1}
do_test view-5.4 {
  execsql {
    SELECT * FROM v5 AS a, t2 AS b WHERE a.w=b.y;
  }
} {1 22 22 2 4 55 55 5}
do_test view-5.5 {
  lsearch [execsql {
    EXPLAIN SELECT * FROM v5 AS a, t2 AS b WHERE a.w=b.y;
  }] OpenTemp
} {-1}
do_test view-5.6 {
  execsql {
    SELECT * FROM t2 AS b, v5 AS a WHERE a.w=b.y;
  }
} {22 2 1 22 55 5 4 55}
do_test view-5.7 {
  lsearch [execsql {
    EXPLAIN SELECT * FROM t2 AS b, v5 AS a WHERE a.w=b.y;
  }] OpenTemp
} {-1}
do_test view-5.8 {
  execsql {
    SELECT * FROM t1 AS a, v5 AS b, t2 AS c WHERE a.x=b.v AND b.w=c.y;
  }
} {1 2 3 4 1 22 22 2 4 5 6 7 4 55 55 5}
do_test view-5.9 {
  lsearch [execsql {
    EXPLAIN SELECT * FROM t1 AS a, v5 AS b, t2 AS c WHERE a.x=b.v AND b.w=c.y;
  }] OpenTemp
} {-1}
} ;# endif explain

do_test view-6.1 {
  execsql {
    SELECT min(x), min(a), min(b), min(c), min(a+b+c) FROM v2;
  }