SQLite

**     COPY
**     VACUUM
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**     PRAGMA
**
** $Id: build.c,v 1.133 2003/03/20 01:16:58 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** This routine is called when a new SQL statement is beginning to
** be parsed.  Check to see if the schema for the database needs

}

/*
** Append a new table name to the given SrcList.  Create a new SrcList if
** need be.  A new entry is created in the SrcList even if pToken is NULL.
**
** A new SrcList is returned, or NULL if malloc() fails.
**
** If pDatabase is not null, it means that the table has an optional
** database name prefix.  Like this:  "database.table".  The pDatabase
** points to the table name and the pTable points to the database name.
** The SrcList.a[].zName field is filled with the table name which might
** come from pTable (if pDatabase is NULL) or from pDatabase.  
** SrcList.a[].zDatabase is filled with the database name from pTable,
** or with NULL if no database is specified.
**
** In other words, if call like this:
**
**         sqliteSrcListAppend(A,B,0);
**
** Then B is a table name and the database name is unspecified.  If called
** like this:
**
**         sqliteSrcListAppend(A,B,C);
**
** Then C is the table name and B is the database name.
*/
SrcList *sqliteSrcListAppend(SrcList *pList, Token *pTable, Token *pDatabase){
  if( pList==0 ){
    pList = sqliteMalloc( sizeof(SrcList) );
    if( pList==0 ) return 0;
  }
  if( (pList->nSrc & 7)==1 ){
    SrcList *pNew;
    pNew = sqliteRealloc(pList,
               sizeof(*pList) + (pList->nSrc+8)*sizeof(pList->a[0]) );
    if( pNew==0 ){
      sqliteSrcListDelete(pList);
      return 0;
    }
    pList = pNew;
  }
  memset(&pList->a[pList->nSrc], 0, sizeof(pList->a[0]));
  if( pDatabase && pDatabase->z==0 ){
    pDatabase = 0;
  }
  if( pDatabase && pTable ){
    Token *pTemp = pDatabase;
    pDatabase = pTable;
    pTable = pTemp;
  }
  if( pTable ){
    char **pz = &pList->a[pList->nSrc].zName;
    sqliteSetNString(pz, pTable->z, pTable->n, 0);
    if( *pz==0 ){
      sqliteSrcListDelete(pList);
      return 0;
    }else{
      sqliteDequote(*pz);
    }
  }
  if( pDatabase ){
    char **pz = &pList->a[pList->nSrc].zDatabase;
    sqliteSetNString(pz, pDatabase->z, pDatabase->n, 0);
    if( *pz==0 ){
      sqliteSrcListDelete(pList);
      return 0;
    }else{
      sqliteDequote(*pz);
    }
  }

/*
** Delete an entire SrcList including all its substructure.
*/
void sqliteSrcListDelete(SrcList *pList){
  int i;
  if( pList==0 ) return;
  for(i=0; i<pList->nSrc; i++){
    sqliteFree(pList->a[i].zDatabase);
    sqliteFree(pList->a[i].zName);
    sqliteFree(pList->a[i].zAlias);
    if( pList->a[i].pTab && pList->a[i].pTab->isTransient ){
      sqliteDeleteTable(0, pList->a[i].pTab);
    }
    sqliteSelectDelete(pList->a[i].pSelect);
    sqliteExprDelete(pList->a[i].pOn);
    sqliteIdListDelete(pList->a[i].pUsing);
  }

  sqliteFree(pList);
}

/*
** The COPY command is for compatibility with PostgreSQL and specificially
** for the ability to read the output of pg_dump.  The format is as
** follows:

** named database files.
*/
void sqliteCodeVerifySchema(Parse *pParse){
  int i;
  sqlite *db = pParse->db;
  Vdbe *v = sqliteGetVdbe(pParse);
  for(i=0; i<db->nDb; i++){
    if( i==1 || db->aDb[i].pBt==0 ) continue;
    sqliteVdbeAddOp(v, OP_VerifyCookie, 0, db->aDb[i].schema_cookie);
  }
  pParse->schemaVerified = 1;
}

/*
** Generate VDBE code that prepares for doing an operation that

**    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 DELETE FROM statements.
**
** $Id: delete.c,v 1.47 2003/03/20 01:16:59 drh Exp $
*/
#include "sqliteInt.h"


/*
** Given a table name, find the corresponding table and make sure the
** table is writeable.  Generate an error and return NULL if not.  If

      " may not be modified", 0);
    pParse->nErr++;
    return 0;      
  }
  return pTab;
}

























/*
** Process a DELETE FROM statement.
*/
void sqliteDeleteFrom(
  Parse *pParse,         /* The parser context */
  SrcList *pTabList,     /* The table from which we should delete things */
  Expr *pWhere           /* The WHERE clause.  May be null */
){
  Vdbe *v;               /* The virtual database engine */
  Table *pTab;           /* The table from which records will be deleted */
  char *zTab;            /* Name of the table from which we are deleting */

  int end, addr;         /* A couple addresses of generated code */
  int i;                 /* Loop counter */
  WhereInfo *pWInfo;     /* Information about the WHERE clause */
  Index *pIdx;           /* For looping over indices of the table */
  int base;              /* Index of the first available table cursor */
  sqlite *db;            /* Main database structure */

  int row_triggers_exist = 0;
  int oldIdx = -1;

  if( pParse->nErr || sqlite_malloc_failed ){
    pTabList = 0;
    goto delete_from_cleanup;
  }
  db = pParse->db;
  assert( pTabList->nSrc==1 );

  /* Check for the special case of a VIEW with one or more ON DELETE triggers 
  ** defined 
  */
  zTab = pTabList->a[0].zName;
  if( zTab != 0 ){
    pTab = sqliteFindTable(pParse->db, zTab);
    if( pTab ){
      row_triggers_exist = 
        sqliteTriggersExist(pParse, pTab->pTrigger, 
            TK_DELETE, TK_BEFORE, TK_ROW, 0) ||
        sqliteTriggersExist(pParse, pTab->pTrigger, 
            TK_DELETE, TK_AFTER, TK_ROW, 0);
    }

    if( row_triggers_exist &&  pTab->pSelect ){
      /* Just fire VIEW triggers */
      sqliteSrcListDelete(pTabList);
      sqliteViewTriggers(pParse, pTab, pWhere, OE_Replace, 0);
      return;
    }
  }

  /* Locate the table which we want to delete.  This table has to be
  ** put in an SrcList structure because some of the subroutines we
  ** will be calling are designed to work with multiple tables and expect
  ** an SrcList* parameter instead of just a Table* parameter.
  */
  pTab = pTabList->a[0].pTab = sqliteTableNameToTable(pParse, zTab);
  if( pTab==0 ){
    goto delete_from_cleanup;


  }
  assert( pTab->pSelect==0 );  /* This table is not a view */
  if( sqliteAuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0) ){
    goto delete_from_cleanup;
  }

  /* Allocate a cursor used to store the old.* data for a trigger.
  */

**    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 1.89 2003/03/20 01:16:59 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Construct a new expression node and return a pointer to it.  Memory
** for this node is obtained from sqliteMalloc().  The calling function

    pNew->a[i].done = 0;
  }
  return pNew;
}
SrcList *sqliteSrcListDup(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 = sqliteMalloc( nByte );
  if( pNew==0 ) return 0;
  pNew->nSrc = p->nSrc;


  for(i=0; i<p->nSrc; i++){
    pNew->a[i].zName = sqliteStrDup(p->a[i].zName);
    pNew->a[i].zAlias = sqliteStrDup(p->a[i].zAlias);
    pNew->a[i].jointype = p->a[i].jointype;
    pNew->a[i].pTab = 0;
    pNew->a[i].pSelect = sqliteSelectDup(p->a[i].pSelect);
    pNew->a[i].pOn = sqliteExprDup(p->a[i].pOn);

**    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 1.74 2003/03/20 01:16:59 drh Exp $
*/
#include "sqliteInt.h"

/*
** This routine is call to handle SQL of the following forms:
**
**    insert into TABLE (IDLIST) values(EXPRLIST)

**         loop over the intermediate table
**           transfer values form intermediate table into <table>
**         end the loop
**         cleanup
*/
void sqliteInsert(
  Parse *pParse,        /* Parser context */
  SrcList *pTabList,    /* Name of table into which we are inserting */
  ExprList *pList,      /* List of values to be inserted */
  Select *pSelect,      /* A SELECT statement to use as the data source */
  IdList *pColumn,      /* Column names corresponding to IDLIST. */
  int onError           /* How to handle constraint errors */
){
  Table *pTab;          /* The table to insert into */
  char *zTab;           /* Name of the table into which we are inserting */
  int i, j, idx;        /* Loop counters */
  Vdbe *v;              /* Generate code into this virtual machine */
  Index *pIdx;          /* For looping over indices of the table */
  int nColumn;          /* Number of columns in the data */
  int base;             /* First available cursor */
  int iCont, iBreak;    /* Beginning and end of the loop over srcTab */
  sqlite *db;           /* The main database structure */

  int newIdx = -1;

  if( pParse->nErr || sqlite_malloc_failed ) goto insert_cleanup;
  db = pParse->db;

  /* Locate the table into which we will be inserting new information.
  */
  assert( pTabList->nSrc==1 );
  zTab = pTabList->a[0].zName;
  if( zTab==0 ) goto insert_cleanup;
  pTab = sqliteFindTable(pParse->db, zTab);
  if( pTab==0 ){
    sqliteSetString(&pParse->zErrMsg, "no such table: ", zTab, 0);
    pParse->nErr++;
    goto insert_cleanup;
  }

    sqliteSetString(&pParse->zErrMsg, 
      pTab->pSelect ? "view " : "table ",
      zTab,
      " may not be modified", 0);
    pParse->nErr++;
    goto insert_cleanup;
  }



  if( pTab==0 ) goto insert_cleanup;

  /* If pTab is really a view, make sure it has been initialized.
  */
  if( pTab->pSelect ){
    if( sqliteViewGetColumnNames(pParse, pTab) ){

    sqliteVdbeAddOp(v, OP_ColumnName, 0, 0);
    sqliteVdbeChangeP3(v, -1, "rows inserted", P3_STATIC);
    sqliteVdbeAddOp(v, OP_MemLoad, iCntMem, 0);
    sqliteVdbeAddOp(v, OP_Callback, 1, 0);
  }

insert_cleanup:
  sqliteSrcListDelete(pTabList);
  if( pList ) sqliteExprListDelete(pList);
  if( pSelect ) sqliteSelectDelete(pSelect);

  sqliteIdListDelete(pColumn);
}

/*
** Generate code to do a constraint check prior to an INSERT or an UPDATE.
**
** When this routine is called, the stack contains (from bottom to top)

**
*************************************************************************
** 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 1.116 2003/03/20 01:16:59 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>

/*
** A pointer to this structure is used to communicate information

      }
    }
    sqliteFree(db);
    sqliteStrRealloc(pzErrMsg);
    return 0;
  }
  db->aDb[0].zName = "main";
  db->aDb[1].zName = "temp";

  /* Attempt to read the schema */
  sqliteRegisterBuiltinFunctions(db);
  rc = sqliteInit(db, pzErrMsg);
  db->magic = SQLITE_MAGIC_OPEN;
  if( sqlite_malloc_failed ){
    sqlite_close(db);

    return;
  }
  db->magic = SQLITE_MAGIC_CLOSED;
  for(j=0; j<db->nDb; j++){
    if( db->aDb[j].pBt ){
      sqliteBtreeClose(db->aDb[j].pBt);
    }
    if( j>=2 ){
      sqliteFree(db->aDb[j].zName);
    }
  }
  if( db->aDb!=db->aDbStatic ){
    sqliteFree(db->aDb);
  }
  sqliteResetInternalSchema(db);
  for(i=sqliteHashFirst(&db->aFunc); i; i=sqliteHashNext(i)){
    FuncDef *pFunc, *pNext;

**
*************************************************************************
** 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 1.92 2003/03/20 01:16:59 drh Exp $
*/
%token_prefix TK_
%token_type {Token}
%default_type {Token}
%extra_argument {Parse *pParse}
%syntax_error {
  if( pParse->zErrMsg==0 ){

id(A) ::= ID(X).         {A = X;}

// The following directive causes tokens ABORT, AFTER, ASC, etc. to
// fallback to ID if they will not parse as their original value.
// This obviates the need for the "id" nonterminal.
//
%fallback ID 
  ABORT AFTER ASC ATTACH BEFORE BEGIN CASCADE CLUSTER CONFLICT
  COPY DATABASE DEFERRED DELIMITERS DESC DETACH EACH END EXPLAIN FAIL FOR
  IGNORE IMMEDIATE INITIALLY INSTEAD MATCH KEY
  OF OFFSET PRAGMA RAISE REPLACE RESTRICT ROW STATEMENT
  TEMP TRIGGER VACUUM VIEW.

// And "ids" is an identifer-or-string.
//
%type ids {Token}

// in a SELECT statement.  "stl_prefix" is a prefix of this list.
//
stl_prefix(A) ::= seltablist(X) joinop(Y).    {
   A = X;
   if( A && A->nSrc>0 ) A->a[A->nSrc-1].jointype = Y;
}
stl_prefix(A) ::= .                           {A = 0;}
seltablist(A) ::= stl_prefix(X) nm(Y) dbnm(D) as(Z) on_opt(N) using_opt(U). {
  A = sqliteSrcListAppend(X,&Y,&D);
  if( Z.n ) sqliteSrcListAddAlias(A,&Z);
  if( N ){
    if( A && A->nSrc>1 ){ A->a[A->nSrc-2].pOn = N; }
    else { sqliteExprDelete(N); }
  }
  if( U ){
    if( A && A->nSrc>1 ){ A->a[A->nSrc-2].pUsing = U; }
    else { sqliteIdListDelete(U); }
  }
}
seltablist(A) ::= stl_prefix(X) LP select(S) RP as(Z) on_opt(N) using_opt(U). {
  A = sqliteSrcListAppend(X,0,0);
  A->a[A->nSrc-1].pSelect = S;
  if( Z.n ) sqliteSrcListAddAlias(A,&Z);
  if( N ){
    if( A && A->nSrc>1 ){ A->a[A->nSrc-2].pOn = N; }
    else { sqliteExprDelete(N); }
  }
  if( U ){
    if( A && A->nSrc>1 ){ A->a[A->nSrc-2].pUsing = U; }
    else { sqliteIdListDelete(U); }
  }
}

%type dbnm {Token}
dbnm(A) ::= .          {A.z=0; A.n=0;}
dbnm(A) ::= DOT nm(X). {A = X;}

%type joinop {int}
%type joinop2 {int}
joinop(X) ::= COMMA.                   { X = JT_INNER; }
joinop(X) ::= JOIN.                    { X = JT_INNER; }
joinop(X) ::= JOIN_KW(A) JOIN.         { X = sqliteJoinType(pParse,&A,0,0); }
joinop(X) ::= JOIN_KW(A) nm(B) JOIN.   { X = sqliteJoinType(pParse,&A,&B,0); }
joinop(X) ::= JOIN_KW(A) nm(B) nm(C) JOIN.

limit_opt(A) ::= LIMIT INTEGER(X) OFFSET INTEGER(Y). 
                                    {A.limit = atoi(X.z); A.offset = atoi(Y.z);}
limit_opt(A) ::= LIMIT INTEGER(X) COMMA INTEGER(Y). 
                                    {A.limit = atoi(Y.z); A.offset = atoi(X.z);}

/////////////////////////// The DELETE statement /////////////////////////////
//
cmd ::= DELETE FROM nm(X) dbnm(D) where_opt(Y). {
   sqliteDeleteFrom(pParse, sqliteSrcListAppend(0,&X,&D), Y);
}

%type where_opt {Expr*}
%destructor where_opt {sqliteExprDelete($$);}

where_opt(A) ::= .                    {A = 0;}
where_opt(A) ::= WHERE expr(X).       {A = X;}

%type setlist {ExprList*}
%destructor setlist {sqliteExprListDelete($$);}

////////////////////////// The UPDATE command ////////////////////////////////
//
cmd ::= UPDATE orconf(R) nm(X) dbnm(D) SET setlist(Y) where_opt(Z).
    {sqliteUpdate(pParse,sqliteSrcListAppend(0,&X,&D),Y,Z,R);}

setlist(A) ::= setlist(Z) COMMA nm(X) EQ expr(Y).
    {A = sqliteExprListAppend(Z,Y,&X);}
setlist(A) ::= nm(X) EQ expr(Y).   {A = sqliteExprListAppend(0,Y,&X);}

////////////////////////// The INSERT command /////////////////////////////////
//
cmd ::= insert_cmd(R) INTO nm(X) dbnm(D) inscollist_opt(F) 
        VALUES LP itemlist(Y) RP.
            {sqliteInsert(pParse, sqliteSrcListAppend(0,&X,&D), Y, 0, F, R);}
cmd ::= insert_cmd(R) INTO nm(X) dbnm(D) inscollist_opt(F) select(S).
            {sqliteInsert(pParse, sqliteSrcListAppend(0,&X,&D), 0, S, F, R);}

%type insert_cmd {int}
insert_cmd(A) ::= INSERT orconf(R).   {A = R;}
insert_cmd(A) ::= REPLACE.            {A = OE_Replace;}


%type itemlist {ExprList*}

  sqliteExprSpan(A, &X, &Y);
}

////////////////////////  DROP TRIGGER statement //////////////////////////////
cmd ::= DROP TRIGGER nm(X). {
    sqliteDropTrigger(pParse,&X,0);
}

//////////////////////// ATTACH DATABASE file AS name /////////////////////////
cmd ::= ATTACH database_kw_opt ids AS nm.

database_kw_opt ::= DATABASE.
database_kw_opt ::= .

//////////////////////// DETACH DATABASE name /////////////////////////////////
cmd ::= DETACH database_kw_opt nm.

/*
** 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 1.164 2003/03/20 01:16:59 drh Exp $
*/
#include "config.h"
#include "sqlite.h"
#include "hash.h"
#include "vdbe.h"
#include "parse.h"
#include "btree.h"

** The following structure describes the FROM clause of a SELECT statement.
** Each table or subquery in the FROM clause is a separate element of
** the SrcList.a[] array.
*/
struct SrcList {
  int nSrc;        /* Number of tables or subqueries in the FROM clause */
  struct SrcList_item {
    char *zDatabase;  /* Name of database holding this table */
    char *zName;      /* Name of the table */
    char *zAlias;     /* The "B" part of a "A AS B" phrase.  zName is the "A" */
    Table *pTab;      /* An SQL table corresponding to zName */
    Select *pSelect;  /* A SELECT statement used in place of a table name */
    int jointype;     /* Type of join between this table and the next */
    Expr *pOn;        /* The ON clause of a join */
    IdList *pUsing;   /* The USING clause of a join */
  } a[1];             /* One entry for each identifier on the list */
};

/*
** Permitted values of the SrcList.a.jointype field
*/
#define JT_INNER     0x0001    /* Any kind of inner or cross join */
#define JT_NATURAL   0x0002    /* True for a "natural" join */

void sqliteAddCollateType(Parse*, int);
void sqliteEndTable(Parse*,Token*,Select*);
void sqliteCreateView(Parse*,Token*,Token*,Select*,int);
int sqliteViewGetColumnNames(Parse*,Table*);
void sqliteViewResetAll(sqlite*);
void sqliteDropTable(Parse*, Token*, int);
void sqliteDeleteTable(sqlite*, Table*);
void sqliteInsert(Parse*, SrcList*, ExprList*, Select*, IdList*, int);
IdList *sqliteIdListAppend(IdList*, Token*);
int sqliteIdListIndex(IdList*,const char*);
SrcList *sqliteSrcListAppend(SrcList*, Token*, Token*);
void sqliteSrcListAddAlias(SrcList*, Token*);
void sqliteIdListDelete(IdList*);
void sqliteSrcListDelete(SrcList*);
void sqliteCreateIndex(Parse*, Token*, Token*, IdList*, int, Token*, Token*);
void sqliteDropIndex(Parse*, Token*);
void sqliteAddKeyType(Vdbe*, ExprList*);
void sqliteAddIdxKeyType(Vdbe*, Index*);
int sqliteSelect(Parse*, Select*, int, int, Select*, int, int*);
Select *sqliteSelectNew(ExprList*,SrcList*,Expr*,ExprList*,Expr*,ExprList*,
                        int,int,int);
void sqliteSelectDelete(Select*);
void sqliteSelectUnbind(Select*);
Table *sqliteTableNameToTable(Parse*, const char*);

void sqliteDeleteFrom(Parse*, SrcList*, Expr*);
void sqliteUpdate(Parse*, SrcList*, ExprList*, Expr*, int);
WhereInfo *sqliteWhereBegin(Parse*, int, SrcList*, Expr*, int, ExprList**);
void sqliteWhereEnd(WhereInfo*);
void sqliteExprCode(Parse*, Expr*);
void sqliteExprIfTrue(Parse*, Expr*, int, int);
void sqliteExprIfFalse(Parse*, Expr*, int, int);
Table *sqliteFindTable(sqlite*,const char*);
Index *sqliteFindIndex(sqlite*,const char*);

*************************************************************************
** An tokenizer for SQL
**
** This file contains C code that splits an SQL input string up into
** individual tokens and sends those tokens one-by-one over to the
** parser for analysis.
**
** $Id: tokenize.c,v 1.56 2003/03/20 01:16:59 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include <stdlib.h>

/*

static Keyword aKeywordTable[] = {
  { "ABORT",             0, TK_ABORT,            0 },
  { "AFTER",             0, TK_AFTER,            0 },
  { "ALL",               0, TK_ALL,              0 },
  { "AND",               0, TK_AND,              0 },
  { "AS",                0, TK_AS,               0 },
  { "ASC",               0, TK_ASC,              0 },
  { "ATTACH",            0, TK_ATTACH,           0 },
  { "BEFORE",            0, TK_BEFORE,           0 },
  { "BEGIN",             0, TK_BEGIN,            0 },
  { "BETWEEN",           0, TK_BETWEEN,          0 },
  { "BY",                0, TK_BY,               0 },
  { "CASCADE",           0, TK_CASCADE,          0 },
  { "CASE",              0, TK_CASE,             0 },
  { "CHECK",             0, TK_CHECK,            0 },
  { "CLUSTER",           0, TK_CLUSTER,          0 },
  { "COLLATE",           0, TK_COLLATE,          0 },
  { "COMMIT",            0, TK_COMMIT,           0 },
  { "CONFLICT",          0, TK_CONFLICT,         0 },
  { "CONSTRAINT",        0, TK_CONSTRAINT,       0 },
  { "COPY",              0, TK_COPY,             0 },
  { "CREATE",            0, TK_CREATE,           0 },
  { "CROSS",             0, TK_JOIN_KW,          0 },
  { "DATABASE",          0, TK_DATABASE,         0 },
  { "DEFAULT",           0, TK_DEFAULT,          0 },
  { "DEFERRED",          0, TK_DEFERRED,         0 },
  { "DEFERRABLE",        0, TK_DEFERRABLE,       0 },
  { "DELETE",            0, TK_DELETE,           0 },
  { "DELIMITERS",        0, TK_DELIMITERS,       0 },
  { "DESC",              0, TK_DESC,             0 },
  { "DETACH",            0, TK_DETACH,           0 },
  { "DISTINCT",          0, TK_DISTINCT,         0 },
  { "DROP",              0, TK_DROP,             0 },
  { "END",               0, TK_END,              0 },
  { "EACH",              0, TK_EACH,             0 },
  { "ELSE",              0, TK_ELSE,             0 },
  { "EXCEPT",            0, TK_EXCEPT,           0 },
  { "EXPLAIN",           0, TK_EXPLAIN,          0 },

	assert(ss);
	assert(ss->pSrc);
	sqliteSelect(pParse, ss, SRT_Discard, 0, 0, 0, 0);
	sqliteSelectDelete(ss);
	break;
      }
      case TK_UPDATE: {
        SrcList *pSrc;
        pSrc = sqliteSrcListAppend(0, &pTriggerStep->target, 0);
        sqliteVdbeAddOp(pParse->pVdbe, OP_ListPush, 0, 0);
        sqliteUpdate(pParse, pSrc,
		sqliteExprListDup(pTriggerStep->pExprList), 
		sqliteExprDup(pTriggerStep->pWhere), orconf);
        sqliteVdbeAddOp(pParse->pVdbe, OP_ListPop, 0, 0);
        break;
      }
      case TK_INSERT: {
        SrcList *pSrc;
        pSrc = sqliteSrcListAppend(0, &pTriggerStep->target, 0);
        sqliteInsert(pParse, pSrc,
          sqliteExprListDup(pTriggerStep->pExprList), 
          sqliteSelectDup(pTriggerStep->pSelect), 
          sqliteIdListDup(pTriggerStep->pIdList), orconf);
        break;
      }
      case TK_DELETE: {
        SrcList *pSrc;
        sqliteVdbeAddOp(pParse->pVdbe, OP_ListPush, 0, 0);
        pSrc = sqliteSrcListAppend(0, &pTriggerStep->target, 0);
        sqliteDeleteFrom(pParse, pSrc, sqliteExprDup(pTriggerStep->pWhere));
        sqliteVdbeAddOp(pParse->pVdbe, OP_ListPop, 0, 0);
        break;
      }
      default:
        assert(0);
    } 
    pParse->nTab = saveNTab;

    if( fire_this && (pTriggerStack = sqliteMalloc(sizeof(TriggerStack)))!=0 ){
      int endTrigger;
      SrcList dummyTablist;
      Expr * whenExpr;

      dummyTablist.nSrc = 0;


      /* Push an entry on to the trigger stack */
      pTriggerStack->pTrigger = pTrigger;
      pTriggerStack->newIdx = newIdx;
      pTriggerStack->oldIdx = oldIdx;
      pTriggerStack->pTab = pTab;
      pTriggerStack->pNext = pParse->trigStack;

  assert(pTab->pSelect);

  tblNameToken.z = pTab->zName;
  tblNameToken.n = strlen(pTab->zName);

  theSelect.isDistinct = 0;
  theSelect.pEList = sqliteExprListAppend(0, sqliteExpr(TK_ALL, 0, 0, 0), 0);
  theSelect.pSrc   = sqliteSrcListAppend(0, &tblNameToken, 0);
  theSelect.pWhere = pWhere;    pWhere = 0;
  theSelect.pGroupBy = 0;
  theSelect.pHaving = 0;
  theSelect.pOrderBy = 0;
  theSelect.op = TK_SELECT; /* ?? */
  theSelect.pPrior = 0;
  theSelect.nLimit = -1;

**    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 1.55 2003/03/20 01:16:59 drh Exp $
*/
#include "sqliteInt.h"

/*
** Process an UPDATE statement.
*/
void sqliteUpdate(
  Parse *pParse,         /* The parser context */
  SrcList *pTabList,     /* The table in which we should change things */
  ExprList *pChanges,    /* Things to be changed */
  Expr *pWhere,          /* The WHERE clause.  May be null */
  int onError            /* How to handle constraint errors */
){
  int i, j;              /* Loop counters */
  char *zTab;            /* Name of the table to be updated */
  Table *pTab;           /* The table to be updated */

  int addr;              /* VDBE instruction address of the start of the loop */
  WhereInfo *pWInfo;     /* Information about the WHERE clause */
  Vdbe *v;               /* The virtual database engine */
  Index *pIdx;           /* For looping over indices */
  int nIdx;              /* Number of indices that need updating */
  int nIdxTotal;         /* Total number of indices */
  int base;              /* Index of first available table cursor */

  int row_triggers_exist = 0;

  int newIdx      = -1;  /* index of trigger "new" temp table       */
  int oldIdx      = -1;  /* index of trigger "old" temp table       */

  if( pParse->nErr || sqlite_malloc_failed ) goto update_cleanup;
  db = pParse->db;
  assert( pTabList->nSrc==1 );

  /* Check for the special case of a VIEW with one or more ON UPDATE triggers 
   * defined 
   */


  zTab = pTabList->a[0].zName;
  if( zTab != 0 ){
    pTab = sqliteFindTable(pParse->db, zTab);
    if( pTab ){
      row_triggers_exist = 
        sqliteTriggersExist(pParse, pTab->pTrigger, 
            TK_UPDATE, TK_BEFORE, TK_ROW, pChanges) ||
        sqliteTriggersExist(pParse, pTab->pTrigger, 
            TK_UPDATE, TK_AFTER, TK_ROW, pChanges);
    }

    if( row_triggers_exist &&  pTab->pSelect ){
      /* Just fire VIEW triggers */
      sqliteSrcListDelete(pTabList);
      sqliteViewTriggers(pParse, pTab, pWhere, onError, pChanges);
      return;

    }
  }

  /* Locate the table which we want to update.  This table has to be
  ** put in an SrcList structure because some of the subroutines we
  ** will be calling are designed to work with multiple tables and expect
  ** an SrcList* parameter instead of just a Table* parameter.
  */
  pTab = pTabList->a[0].pTab = sqliteTableNameToTable(pParse, zTab);
  if( pTab==0 ) goto update_cleanup;

  assert( pTab->pSelect==0 );  /* This table is not a VIEW */
  aXRef = sqliteMalloc( sizeof(int) * pTab->nCol );
  if( aXRef==0 ) goto update_cleanup;
  for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;

  /* If there are FOR EACH ROW triggers, allocate temp tables */
  if( row_triggers_exist ){

**
** 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 1.209 2003/03/20 01:16:59 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The makefile scans this source file and creates the following
** array of string constants which are the names of all VDBE opcodes.

}

/*
** Delete an entire VDBE.
*/
void sqliteVdbeDelete(Vdbe *p){
  int i;

  if( p==0 ) return;
  Cleanup(p);
  if( p->pPrev ){
    p->pPrev->pNext = p->pNext;
  }else{
    assert( p->db->pVdbe==p );
    p->db->pVdbe = p->pNext;

    p->nOp = 0;
  }
  for(i=0; i<p->nOp; i++){
    if( p->aOp[i].p3type==P3_DYNAMIC ){
      sqliteFree(p->aOp[i].p3);
    }
  }







  sqliteFree(p->aOp);
  sqliteFree(p->aLabel);
  sqliteFree(p->aStack);
  sqliteFree(p);
}

/*

void sqliteVdbeMakeReady(
  Vdbe *p,                       /* The VDBE */
  sqlite_callback xCallback,     /* Result callback */
  void *pCallbackArg,            /* 1st argument to xCallback() */
  int isExplain                  /* True if the EXPLAIN keywords is present */
){
  int n;
#ifdef MEMORY_DEBUG
  extern int access(const char*,int);
#endif

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

  /* Add a HALT instruction to the very end of the program.
  */

** Either a transaction needs to have been started or an OP_Open needs
** to be executed (to establish a read lock) before this opcode is
** invoked.
*/
case OP_VerifyCookie: {
  int aMeta[SQLITE_N_BTREE_META];
  assert( pOp->p1>=0 && pOp->p1<db->nDb );

  rc = sqliteBtreeGetMeta(db->aDb[pOp->p1].pBt, aMeta);
  if( rc==SQLITE_OK && aMeta[1]!=pOp->p2 ){
    sqliteSetString(&p->zErrMsg, "database schema has changed", 0);
    rc = SQLITE_SCHEMA;
  }
  break;
}