SQLite

**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.295 2005/01/19 23:24:50 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

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

  pCol = &(p->aCol[p->nCol-1]);
  if( !sqlite3ExprIsConstant(pExpr) ){
    sqlite3ErrorMsg(pParse, "default value of column [%s] is not constant",
        pCol->zName);
  }else{
    sqlite3ExprDelete(pCol->pDflt);
    pCol->pDflt = sqlite3ExprDup(pExpr);
    sqlite3ExprResolveNames(pParse,0,0,0,pExpr,0,0);
  }
  sqlite3ExprDelete(pExpr);
}

/*
** Designate the PRIMARY KEY for the table.  pList is a list of names 
** of columns that form the primary key.  If pList is NULL, then the

    */
    if( pSelect ){
      Table *pSelTab;
      sqlite3VdbeAddOp(v, OP_Dup, 0, 0);
      sqlite3VdbeAddOp(v, OP_Integer, p->iDb, 0);
      sqlite3VdbeAddOp(v, OP_OpenWrite, 1, 0);
      pParse->nTab = 2;
      sqlite3Select(pParse, pSelect, SRT_Table, 1, 0, 0, 0, 0, 0);
      sqlite3VdbeAddOp(v, OP_Close, 1, 0);
      if( pParse->nErr==0 ){
        pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSelect);
        if( pSelTab==0 ) return;
        assert( p->aCol==0 );
        p->nCol = pSelTab->nCol;
        p->aCol = pSelTab->aCol;

**    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 1.98 2005/01/19 23:24:50 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.

    oldIdx = pParse->nTab++;
  }

  /* Resolve the column names in all the expressions.
  */
  assert( pTabList->nSrc==1 );
  iCur = pTabList->a[0].iCursor = pParse->nTab++;
  if( sqlite3ExprResolveNames(pParse, pTabList, 0, 0, pWhere, 0, 1) ){
    goto delete_from_cleanup;
  }

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

  sqlite3BeginWriteOperation(pParse, triggers_exist, pTab->iDb);

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

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

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains routines used for analyzing expressions and
** for generating VDBE code that evaluates expressions in SQLite.
**
** $Id: expr.c,v 1.182 2005/01/19 23:24:50 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

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

      */
      return is_agg;
    }
  }
  return 0;
}

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

/*
** This routine walks an expression tree and resolves references to
** table columns.  Nodes of the form ID.ID or ID resolve into an
** index to the table in the table list and a column offset.  The 
** Expr.opcode for such nodes is changed to TK_COLUMN.  The Expr.iTable
** value is changed to the index of the referenced table in pTabList
** plus the "base" value.  The base value will ultimately become the

** have the correct number of arguments.  Leave an error message
** in pParse->zErrMsg if anything is amiss.  Return the number of errors.
**
** If the expression contains aggregate functions then set the EP_Agg
** property on the expression.
*/
int sqlite3ExprResolveNames(
  Parse *pParse,          /* The parser context */
  SrcList *pSrcList,      /* List of tables used to resolve column names */
  ExprList *pEList,       /* List of expressions used to resolve "AS" */
  NameContext *pNC,       /* Namespace of enclosing statement */
  Expr *pExpr,            /* The expression to be analyzed. */
  int allowAgg,           /* True to allow aggregate expressions */
  int codeSubquery        /* If true, then generate code for subqueries too */
){
  NameContext sNC;

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

/*
** A pointer instance of this structure is used to pass information
** through walkExprTree into codeSubqueryStep().
*/
typedef struct QueryCoder QueryCoder;
struct QueryCoder {
  Parse *pParse;       /* The parsing context */
  NameContext *pNC;    /* Namespace of first enclosing query */
};


/*
** Generate code for subqueries and IN operators.
**
** IN operators comes in two forms:
**

** into a memory cell.
**
** This routine is a callback for wallExprTree() used to implement
** sqlite3ExprCodeSubquery().  See comments on those routines for
** additional information.
*/
static int codeSubqueryStep(void *pArg, Expr *pExpr){
  QueryCoder *pCoder = (QueryCoder*)pArg;
  Parse *pParse = pCoder->pParse;

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

        **
        ** Generate code to write the results of the select into the temporary
        ** table allocated and opened above.
        */
        int iParm = pExpr->iTable +  (((int)affinity)<<16);
        ExprList *pEList;
        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
        sqlite3Select(pParse, pExpr->pSelect, SRT_Set, iParm, 0, 0, 0, 0, 0);
        pEList = pExpr->pSelect->pEList;
        if( pEList && pEList->nExpr>0 ){ 
          keyInfo.aColl[0] = binaryCompareCollSeq(pParse, pExpr->pLeft,
              pEList->a[0].pExpr);
        }
      }else if( pExpr->pList ){
        /* Case 2:     expr IN (exprlist)

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

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

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

      pNC = pCoder->pNC;
      if( pNC ) nRef = pNC->nRef;
      v = sqlite3GetVdbe(pParse);
      addr = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
      pExpr->iColumn = pParse->nMem++;
      sqlite3Select(pParse, pExpr->pSelect, SRT_Mem,pExpr->iColumn,0,0,0,0,pNC);
      if( pNC && pNC->nRef>nRef ){
        /* Subquery value changes.  Evaluate at each use */
        pExpr->iTable = addr+1;
        sqlite3VdbeAddOp(v, OP_Return, 0, 0);
        sqlite3VdbeChangeP2(v, addr, sqlite3VdbeCurrentAddr(v));
      }else{
        /* Subquery value is constant.  evaluate only once. */
        pExpr->iTable = -1;
        sqlite3VdbeChangeP2(v, addr, addr+1);
      }
      return 1;
    }
  }
  return 0;
}

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

/*
** Generate an instruction that will put the integer describe by
** text z[0..n-1] on the stack.
*/

        if( !pColl ) pColl = pParse->db->pDfltColl; 
        sqlite3VdbeOp3(v, OP_CollSeq, 0, 0, (char *)pColl, P3_COLLSEQ);
      }
      sqlite3VdbeOp3(v, OP_Function, nExpr, p2, (char*)pDef, P3_FUNCDEF);
      break;
    }
    case TK_SELECT: {
      if( pExpr->iTable>=0 ){
        sqlite3VdbeAddOp(v, OP_Gosub, 0, pExpr->iTable);
        VdbeComment((v, "# run subquery"));
      }
      sqlite3VdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0);
      VdbeComment((v, "# load subquery result"));
      break;
    }
    case TK_IN: {
      int addr;
      char affinity;

**    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 1.133 2005/01/19 23:24:50 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:

  if( pSelect ){
    /* Data is coming from a SELECT.  Generate code to implement that SELECT
    */
    int rc, iInitCode;
    iInitCode = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
    iSelectLoop = sqlite3VdbeCurrentAddr(v);
    iInsertBlock = sqlite3VdbeMakeLabel(v);
    rc = sqlite3Select(pParse, pSelect, SRT_Subroutine, iInsertBlock,0,0,0,0,0);
    if( rc || pParse->nErr || sqlite3_malloc_failed ) goto insert_cleanup;
    iCleanup = sqlite3VdbeMakeLabel(v);
    sqlite3VdbeAddOp(v, OP_Goto, 0, iCleanup);
    assert( pSelect->pEList );
    nColumn = pSelect->pEList->nExpr;

    /* Set useTempTable to TRUE if the result of the SELECT statement

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

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

  return SQLITE_OK;
}

/*
** The fsync() system call does not work as advertised on many
** unix systems.  The following procedure is an attempt to make
** it work better.
**
** The SQLITE_NO_SYNC macro disables all fsync()s.  This is useful
** for testing when we want to run through the test suite quickly.
** You are strongly advised *not* to deploy with SQLITE_NO_SYNC
** enabled, however, since with SQLITE_NO_SYNC enabled, an OS crash
** or power failure will likely corrupt the database file.
*/
static int full_fsync(int fd){
#ifdef SQLITE_NO_SYNC
  return SQLITE_OK;
#else
  int rc;
#ifdef F_FULLFSYNC
  rc = fcntl(fd, F_FULLFSYNC, 0);
  if( rc ) rc = fsync(fd);
#else
  rc = fsync(fd);
#endif
  return rc;
#endif
}

/*
** Make sure all writes to a particular file are committed to disk.
**
** Under Unix, also make sure that the directory entry for the file
** has been created by fsync-ing the directory that contains the file.

**
*************************************************************************
** This file contains SQLite's grammar for SQL.  Process this file
** using the lemon parser generator to generate C code that runs
** the parser.  Lemon will also generate a header file containing
** numeric codes for all of the tokens.
**
** @(#) $Id: parse.y,v 1.159 2005/01/19 23:24:50 drh Exp $
*/
%token_prefix TK_
%token_type {Token}
%default_type {Token}
%extra_argument {Parse *pParse}
%syntax_error {
  if( pParse->zErrMsg==0 ){

  sqlite3DropTable(pParse, X, 1);
}
%endif // SQLITE_OMIT_VIEW

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

%type select {Select*}
%destructor select {sqlite3SelectDelete($$);}
%type oneselect {Select*}
%destructor oneselect {sqlite3SelectDelete($$);}

**    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 1.229 2005/01/19 23:24:50 drh Exp $
*/
#include "sqliteInt.h"


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

** The declaration type for a ROWID field is INTEGER.
*/
static const char *columnType(Parse *pParse, SrcList *pTabList, Expr *pExpr){
  char const *zType;
  int j;
  if( pExpr==0 || pTabList==0 ) return 0;

  sqlite3ExprResolveNames(pParse, pTabList, 0, 0, pExpr, 1, 0);
  switch( pExpr->op ){
    case TK_COLUMN: {
      Table *pTab;
      int iCol = pExpr->iColumn;
      for(j=0; j<pTabList->nSrc && pTabList->a[j].iCursor!=pExpr->iTable; j++){}
      assert( j<pTabList->nSrc );
      pTab = pTabList->a[j].pTab;

  /* Generate code for the left and right SELECT statements.
  */
  switch( p->op ){
    case TK_ALL: {
      if( p->pOrderBy==0 ){
        pPrior->nLimit = p->nLimit;
        pPrior->nOffset = p->nOffset;
        rc = sqlite3Select(pParse, pPrior, eDest, iParm, 0, 0, 0, aff, 0);
        if( rc ){
          goto multi_select_end;
        }
        p->pPrior = 0;
        p->iLimit = pPrior->iLimit;
        p->iOffset = pPrior->iOffset;
        p->nLimit = -1;
        p->nOffset = 0;
        rc = sqlite3Select(pParse, p, eDest, iParm, 0, 0, 0, aff, 0);
        p->pPrior = pPrior;
        if( rc ){
          goto multi_select_end;
        }
        break;
      }
      /* For UNION ALL ... ORDER BY fall through to the next case */

	assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
        aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, unionTab, 0);
        assert( p->pEList );
      }

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

      /* Code the current SELECT statement
      */
      switch( p->op ){
         case TK_EXCEPT:  op = SRT_Except;   break;
         case TK_UNION:   op = SRT_Union;    break;
         case TK_ALL:     op = SRT_Table;    break;
      }
      p->pPrior = 0;
      pOrderBy = p->pOrderBy;
      p->pOrderBy = 0;
      nLimit = p->nLimit;
      p->nLimit = -1;
      nOffset = p->nOffset;
      p->nOffset = 0;
      rc = sqlite3Select(pParse, p, op, unionTab, 0, 0, 0, aff, 0);
      p->pPrior = pPrior;
      p->pOrderBy = pOrderBy;
      p->nLimit = nLimit;
      p->nOffset = nOffset;
      p->iLimit = -1;
      p->iOffset = -1;
      if( rc ){

      sqlite3VdbeAddOp(v, OP_KeyAsData, tab1, 1);
      assert( nAddr<sizeof(aAddr)/sizeof(aAddr[0]) );
      aAddr[nAddr++] = sqlite3VdbeAddOp(v, OP_SetNumColumns, tab1, 0);
      assert( p->pEList );

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

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

** corresponding entry in the result set.
*/
static int processOrderGroupBy(
  Parse *pParse,        /* Parsing context */
  ExprList *pOrderBy,   /* The ORDER BY or GROUP BY clause to be processed */
  SrcList *pTabList,    /* The FROM clause */
  ExprList *pEList,     /* The result set */
  NameContext *pNC,     /* Name context for enclosing query */
  int isAgg,            /* True if aggregate functions are involved */
  const char *zType     /* Either "ORDER" or "GROUP", as appropriate */
){
  int i;
  if( pOrderBy==0 ) return 0;
  for(i=0; i<pOrderBy->nExpr; i++){
    int iCol;
    Expr *pE = pOrderBy->a[i].pExpr;
    if( sqlite3ExprIsInteger(pE, &iCol) && iCol>0 && iCol<=pEList->nExpr ){
      sqlite3ExprDelete(pE);
      pE = pOrderBy->a[i].pExpr = sqlite3ExprDup(pEList->a[iCol-1].pExpr);
    }
    if( sqlite3ExprResolveNames(pParse, pTabList, pEList, pNC, pE, isAgg, 1) ){
      return 1;
    }
    if( sqlite3ExprIsConstant(pE) ){
      if( sqlite3ExprIsInteger(pE, &iCol)==0 ){
        sqlite3ErrorMsg(pParse,
          "%s BY terms must not be non-integer constants", zType);
        return 1;

  Parse *pParse,         /* The parser context */
  Select *p,             /* The SELECT statement being coded. */
  int eDest,             /* How to dispose of the results */
  int iParm,             /* A parameter used by the eDest disposal method */
  Select *pParent,       /* Another SELECT for which this is a sub-query */
  int parentTab,         /* Index in pParent->pSrc of this query */
  int *pParentAgg,       /* True if pParent uses aggregate functions */
  char *aff,             /* If eDest is SRT_Union, the affinity string */
  NameContext *pNC       /* Namespace of the next outer query */
){
  int i;
  WhereInfo *pWInfo;
  Vdbe *v;
  int isAgg = 0;         /* True for select lists like "count(*)" */
  ExprList *pEList;      /* List of columns to extract. */
  SrcList *pTabList;     /* List of tables to select from */

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

  /* We cannot use a SQL cursor on a join or on a DISTINCT query
  */
#ifndef SQLITE_OMIT_CURSOR

      zSavedAuthContext = pParse->zAuthContext;
      pParse->zAuthContext = pTabList->a[i].zName;
      needRestoreContext = 1;
    }else{
      needRestoreContext = 0;
    }
    sqlite3Select(pParse, pTabList->a[i].pSelect, SRT_TempTable, 
                 pTabList->a[i].iCursor, p, i, &isAgg, 0, 0);
    if( needRestoreContext ){
      pParse->zAuthContext = zSavedAuthContext;
    }
    pTabList = p->pSrc;
    pWhere = p->pWhere;
    if( eDest!=SRT_Union && eDest!=SRT_Except && eDest!=SRT_Discard ){
      pOrderBy = p->pOrderBy;

/*
** 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 1.357 2005/01/19 23:24:51 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

** it can be accessed after all aggregates are computed.
**
** If the expression is a function, the Expr.iTable is an integer code
** representing which function.  If the expression is an unbound variable
** marker (a question mark character '?' in the original SQL) then the
** Expr.iTable holds the index number for that variable.
**
** If the expression is a subquery then Expr.iColumn holds an integer
** register number containing the result of the subquery.  If the
** subquery gives a constant result, then iTable is -1.  If the subquery
** gives a different answer at different times during statement processing
** then iTable is the address of a subroutine that computes the subquery.
**
** The Expr.pSelect field points to a SELECT statement.  The SELECT might
** be the right operand of an IN operator.  Or, if a scalar SELECT appears
** in an expression the opcode is TK_SELECT and Expr.pSelect is the only
** operand.
*/
struct Expr {
  u8 op;                 /* Operation performed by this node */

void sqlite3IdListDelete(IdList*);
void sqlite3SrcListDelete(SrcList*);
void sqlite3CreateIndex(Parse*,Token*,Token*,SrcList*,ExprList*,int,Token*,
                        Token*);
void sqlite3DropIndex(Parse*, SrcList*);
void sqlite3AddKeyType(Vdbe*, ExprList*);
void sqlite3AddIdxKeyType(Vdbe*, Index*);
int sqlite3Select(Parse*, Select*, int, int, Select*, int, int*,
                  char *aff, NameContext*);
Select *sqlite3SelectNew(ExprList*,SrcList*,Expr*,ExprList*,Expr*,ExprList*,
                        int,int,int);
void sqlite3SelectDelete(Select*);
void sqlite3SelectUnbind(Select*);
Table *sqlite3SrcListLookup(Parse*, SrcList*);
int sqlite3IsReadOnly(Parse*, Table*, int);
void sqlite3OpenTableForReading(Vdbe*, int iCur, Table*);

void sqlite3UnlinkAndDeleteIndex(sqlite3*,int,const char*);
void sqlite3Vacuum(Parse*, Token*);
int sqlite3RunVacuum(char**, sqlite3*);
char *sqlite3NameFromToken(Token*);
int sqlite3ExprCheck(Parse*, Expr*, int, int*);
int sqlite3ExprCompare(Expr*, Expr*);
int sqliteFuncId(Token*);
int sqlite3ExprResolveNames(Parse*, SrcList*, ExprList*, NameContext*,
                            Expr*, int, int);
int sqlite3ExprAnalyzeAggregates(Parse*, Expr*);
Vdbe *sqlite3GetVdbe(Parse*);
void sqlite3Randomness(int, void*);
void sqlite3RollbackAll(sqlite3*);
void sqlite3CodeVerifySchema(Parse*, int);
void sqlite3BeginTransaction(Parse*, int);
void sqlite3CommitTransaction(Parse*);

**    May you share freely, never taking more than you give.
**
*************************************************************************
** Code for testing the printf() interface to SQLite.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** $Id: test1.c,v 1.123 2005/01/19 23:24:51 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include "os.h"
#include <stdlib.h>
#include <string.h>

     { "add_test_collate_needed", test_collate_needed, 0     },
     { "add_test_function",       test_function, 0           },
#endif
     { "sqlite3_crashparams",     sqlite3_crashparams, 0     },
     { "sqlite3_test_errstr",     test_errstr, 0             },
     { "tcl_variable_type",       tcl_variable_type, 0       },
  };
  static int bitmask_size = sizeof(Bitmask)*8;
  int i;
  extern int sqlite3_os_trace;
 

  for(i=0; i<sizeof(aCmd)/sizeof(aCmd[0]); i++){
    Tcl_CreateCommand(interp, aCmd[i].zName, aCmd[i].xProc, 0, 0);
  }
  for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, 
        aObjCmd[i].xProc, aObjCmd[i].clientData, 0);

      (char*)&sqlite3_current_time, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_os_trace",
      (char*)&sqlite3_os_trace, TCL_LINK_INT);
  Tcl_LinkVar(interp, "sqlite_static_bind_value",
      (char*)&sqlite_static_bind_value, TCL_LINK_STRING);
  Tcl_LinkVar(interp, "sqlite_temp_directory",
      (char*)&sqlite3_temp_directory, TCL_LINK_STRING);
  Tcl_LinkVar(interp, "bitmask_size",
      (char*)&bitmask_size, TCL_LINK_INT|TCL_LINK_READ_ONLY);
  set_options(interp);
  return TCL_OK;
}

    orconf = (orconfin == OE_Default)?pTriggerStep->orconf:orconfin;
    pParse->trigStack->orconf = orconf;
    switch( pTriggerStep->op ){
      case TK_SELECT: {
	Select * ss = sqlite3SelectDup(pTriggerStep->pSelect);		  
	assert(ss);
	assert(ss->pSrc);
	sqlite3Select(pParse, ss, SRT_Discard, 0, 0, 0, 0, 0, 0);
	sqlite3SelectDelete(ss);
	break;
      }
      case TK_UPDATE: {
        SrcList *pSrc;
        pSrc = targetSrcList(pParse, pTriggerStep);
        sqlite3VdbeAddOp(v, OP_ResetCount, 0, 0);

      trigStackEntry.ignoreJump = ignoreJump;
      pParse->trigStack = &trigStackEntry;
      sqlite3AuthContextPush(pParse, &sContext, pTrigger->name);

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

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

/*
** Process an UPDATE statement.
**
**   UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;

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

      aIdxUsed[j] = 0;
    }
  }

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

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

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

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

** 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 1.130 2005/01/19 23:24:51 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.

** 57->5, 73->4.  Or one of 719 other combinations might be used. It
** does not really matter.  What is important is that sparse cursor
** numbers all get mapped into bit numbers that begin with 0 and contain
** no gaps.
*/
typedef struct ExprMaskSet ExprMaskSet;
struct ExprMaskSet {
  int n;                        /* Number of assigned cursor values */
  int ix[sizeof(Bitmask)*8];    /* Cursor assigned to each bit */
};

/*
** Determine the number of elements in an array.
*/
#define ARRAYSIZE(X)  (sizeof(X)/sizeof(X[0]))

/*
** Initialize an expression mask set
*/
#define initMaskSet(P)  memset(P, 0, sizeof(*P))

/*
** Return the bitmask for the given cursor number.  Return 0 if
** iCursor is not in the set.
*/
static Bitmask getMask(ExprMaskSet *pMaskSet, int iCursor){
  int i;
  for(i=0; i<pMaskSet->n; i++){
    if( pMaskSet->ix[i]==iCursor ){
      return ((Bitmask)1)<<i;
    }
  }
  return 0;
}

/*
** Create a new mask for cursor iCursor.
*/
static void createMask(ExprMaskSet *pMaskSet, int iCursor){
  if( pMaskSet->n<ARRAYSIZE(pMaskSet->ix) ){
    pMaskSet->ix[pMaskSet->n++] = iCursor;


  }

}

/*
** Destroy an expression mask set
*/
#define freeMaskSet(P)   /* NO-OP */

/*

** the VDBE cursor number of the table.
*/
static Bitmask exprTableUsage(ExprMaskSet *pMaskSet, Expr *p){
  Bitmask mask = 0;
  if( p==0 ) return 0;
  if( p->op==TK_COLUMN ){
    mask = getMask(pMaskSet, p->iTable);

    return mask;
  }
  if( p->pRight ){
    mask = exprTableUsage(pMaskSet, p->pRight);
  }
  if( p->pLeft ){
    mask |= exprTableUsage(pMaskSet, p->pLeft);

  ExprMaskSet maskSet; /* The expression mask set */
  int iDirectEq[BMS];  /* Term of the form ROWID==X for the N-th table */
  int iDirectLt[BMS];  /* Term of the form ROWID<X or ROWID<=X */
  int iDirectGt[BMS];  /* Term of the form ROWID>X or ROWID>=X */
  ExprInfo aExpr[101]; /* The WHERE clause is divided into these terms */
  struct SrcList_item *pTabItem;  /* A single entry from pTabList */
  WhereLevel *pLevel;             /* A single level in the pWInfo list */

  /* The number of terms in the FROM clause is limited by the number of
  ** bits in a Bitmask 
  */
  if( pTabList->nSrc>sizeof(Bitmask)*8 ){
    sqlite3ErrorMsg(pParse, "at most %d tables in a join",
       sizeof(Bitmask)*8);
    return 0;
  }

  /* Split the WHERE clause into separate subexpressions where each
  ** subexpression is separated by an AND operator.  If the aExpr[]
  ** array fills up, the last entry might point to an expression which
  ** contains additional unfactored AND operators.
  */
  initMaskSet(&maskSet);
  memset(aExpr, 0, sizeof(aExpr));
  nExpr = exprSplit(ARRAYSIZE(aExpr), aExpr, pWhere);
  if( nExpr==ARRAYSIZE(aExpr) ){
    sqlite3ErrorMsg(pParse, "WHERE clause too complex - no more "
       "than %d terms allowed", (int)ARRAYSIZE(aExpr)-1);
    return 0;
  }
    
  /* Allocate and initialize the WhereInfo structure that will become the
  ** return value.
  */
  pWInfo = sqliteMalloc( sizeof(WhereInfo) + pTabList->nSrc*sizeof(WhereLevel));
  if( sqlite3_malloc_failed ){
    /* sqliteFree(pWInfo); // Leak memory when malloc fails */
    return 0;

  if( pWhere && (pTabList->nSrc==0 || sqlite3ExprIsConstant(pWhere)) ){
    sqlite3ExprIfFalse(pParse, pWhere, pWInfo->iBreak, 1);
    pWhere = 0;
  }

  /* Analyze all of the subexpressions.
  */
  for(i=0; i<pTabList->nSrc; i++){
    createMask(&maskSet, pTabList->a[i].iCursor);
  }
  for(pTerm=aExpr, i=0; i<nExpr; i++, pTerm++){
    TriggerStack *pStack;
    exprAnalyze(pTabList, &maskSet, pTerm);



















  }

  /* Figure out what index to use (if any) for each nested loop.
  ** Make pWInfo->a[i].pIdx point to the index to use for the i-th nested
  ** loop where i==0 is the outer loop and i==pTabList->nSrc-1 is the inner
  ** loop. 
  **

#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# This file implements tests for joins, including outer joins, where
# there are a large number of tables involved in the join.
#
# $Id: join3.test,v 1.4 2005/01/19 23:24:51 drh Exp $

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

# An unrestricted join
#
catch {unset ::result}
set result {}
for {set N 1} {$N<=$bitmask_size} {incr N} {
  lappend result $N
  do_test join3-1.$N {
    execsql "CREATE TABLE t${N}(x);"
    execsql "INSERT INTO t$N VALUES($N)"
    set sql "SELECT * FROM t1"
    for {set i 2} {$i<=$N} {incr i} {append sql ", t$i"}
    execsql $sql
  } $result
}

# Joins with a comparison
#
set result {}
for {set N 1} {$N<=$bitmask_size} {incr N} {
  lappend result $N
  do_test join3-2.$N {
    set sql "SELECT * FROM t1"
    for {set i 2} {$i<=$N} {incr i} {append sql ", t$i"}
    set sep WHERE
    for {set i 1} {$i<$N} {incr i} {
      append sql " $sep t[expr {$i+1}].x==t$i.x+1"
      set sep AND
    }
    execsql $sql
  } $result
}

# Error of too many tables in the join
#
do_test join3-3.1 {
  set sql "SELECT * FROM t1 AS t0, t1"
  for {set i 2} {$i<=$bitmask_size} {incr i} {append sql ", t$i"}
  catchsql $sql
} [list 1 "at most $bitmask_size tables in a join"]


finish_test

      delete from t1 WHERE a=old.a+2;
    end;
    delete from t1 where a in (1,3);
    select * from t1;
    drop table t1;
  }
} {2 b 4 d}

do_test trigger1-1.11 {
  execsql {
    create table t1(a,b);
    insert into t1 values(1,'a');
    insert into t1 values(2,'b');
    insert into t1 values(3,'c');
    insert into t1 values(4,'d');