SQLite

**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**     PRAGMA
**
** $Id: build.c,v 1.210 2004/06/09 00:48:12 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

    }
  }
  pParse->nVar = 0;
}

/*
** This routine is called after a single SQL statement has been
** parsed and a VDBE program to execute that statement has been
** prepared.  This routine puts the finishing touches on the
** VDBE program and resets the pParse structure for the next
** parse.
**
** Note that if an error occurred, it might be the case that
** no VDBE code was generated.
*/
void sqlite3FinishCoding(Parse *pParse){
  sqlite *db;
  Vdbe *v;

  if( sqlite3_malloc_failed ) return;

  /* Begin by generating some termination code at the end of the
  ** vdbe program
  */
  db = pParse->db;
  v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3VdbeAddOp(v, OP_Halt, 0, 0);
    if( pParse->cookieMask!=0 ){
      u32 mask;
      int iDb;
      sqlite3VdbeChangeP2(v, pParse->cookieGoto, sqlite3VdbeCurrentAddr(v));
      for(iDb=0, mask=1; iDb<db->nDb; mask<<=1, iDb++){
        if( (mask & pParse->cookieMask)==0 ) continue;
        sqlite3VdbeAddOp(v, OP_Transaction, iDb, (mask & pParse->writeMask)!=0);
        if( iDb!=1 ){
          sqlite3VdbeAddOp(v, OP_VerifyCookie, iDb, pParse->cookieValue[iDb]);
        }
      }
      sqlite3VdbeAddOp(v, OP_Goto, 0, pParse->cookieGoto+1);
    }
  }

  /* Get the VDBE program ready for execution
  */
  if( v && pParse->nErr==0 ){
    FILE *trace = (db->flags & SQLITE_VdbeTrace)!=0 ? stdout : 0;
    sqlite3VdbeTrace(v, trace);
    sqlite3VdbeMakeReady(v, pParse->nVar, pParse->explain);
    pParse->rc = pParse->nErr ? SQLITE_ERROR : SQLITE_DONE;
    pParse->colNamesSet = 0;
  }else if( pParse->rc==SQLITE_OK ){
    pParse->rc = SQLITE_ERROR;
  }
  pParse->nTab = 0;
  pParse->nMem = 0;
  pParse->nSet = 0;
  pParse->nAgg = 0;
  pParse->nVar = 0;
  pParse->cookieMask = 0;
}

/*
** Locate the in-memory structure that describes 
** a particular database table given the name
** of that table and (optionally) the name of the database
** containing the table.  Return NULL if not found.

  v = sqlite3GetVdbe(pParse);
  if( v ){
    sqlite3VdbeAddOp(v, OP_AutoCommit, 1, 1);
  }
}

/*
** Generate VDBE code that will verify the schema cookie and start
** a read-transaction for all named database files.
**
** It is important that all schema cookies be verified and all
** read transactions be started before anything else happens in
** the VDBE program.  But this routine can be called after much other
** code has been generated.  So here is what we do:
**
** The first time this routine is called, we code an OP_Gosub that
** will jump to a subroutine at the end of the program.  Then we
** record every database that needs its schema verified in the
** pParse->cookieMask field.  Later, after all other code has been
** generated, the subroutine that does the cookie verifications and
** starts the transactions will be coded and the OP_Gosub P2 value
** will be made to point to that subroutine.  The generation of the
** cookie verification subroutine code happens in sqlite3FinishCoding().
*/
void sqlite3CodeVerifySchema(Parse *pParse, int iDb){
  sqlite *db;
  Vdbe *v;
  int mask;

  v = sqlite3GetVdbe(pParse);
  if( v==0 ) return;  /* This only happens if there was a prior error */
  db = pParse->db;
  assert( iDb>=0 && iDb<db->nDb );
  assert( db->aDb[iDb].pBt!=0 || iDb==1 );
  assert( iDb<32 );
  if( pParse->cookieMask==0 ){
    pParse->cookieGoto = sqlite3VdbeAddOp(v, OP_Goto, 0, 0);
  }
  mask = 1<<iDb;
  if( (pParse->cookieMask & mask)==0 ){
    pParse->cookieMask |= mask;
    pParse->cookieValue[iDb] = db->aDb[iDb].schema_cookie;
  }
}

/*
** Generate VDBE code that prepares for doing an operation that
** might change the database.
**

** iDb==1 then only the temp database is made writable.  If iDb>1 then the
** specified auxiliary database and the temp database are made writable.
*/
void sqlite3BeginWriteOperation(Parse *pParse, int setStatement, int iDb){
  sqlite *db = pParse->db;
  Vdbe *v = sqlite3GetVdbe(pParse);
  if( v==0 ) return;
  sqlite3CodeVerifySchema(pParse, iDb);


  pParse->writeMask |= 1<<iDb;

  if( setStatement ){
    sqlite3VdbeAddOp(v, OP_Statement, iDb, 0);
  }
  if( iDb!=1 ){
    sqlite3BeginWriteOperation(pParse, setStatement, 1);
  }
}

**
*************************************************************************
** 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 1.126 2004/06/09 00:48:13 drh Exp $
*/
%token_prefix TK_
%token_type {Token}
%default_type {Token}
%extra_argument {Parse *pParse}
%syntax_error {
  if( pParse->zErrMsg==0 ){

// Input is a single SQL command
input ::= cmdlist.
cmdlist ::= cmdlist ecmd.
cmdlist ::= ecmd.
ecmd ::= explain cmdx SEMI.
ecmd ::= SEMI.
cmdx ::= cmd.           { sqlite3FinishCoding(pParse); }
explain ::= EXPLAIN.    { sqlite3BeginParse(pParse, 1); }
explain ::= .           { sqlite3BeginParse(pParse, 0); }

///////////////////// Begin and end transactions. ////////////////////////////
//

cmd ::= BEGIN trans_opt.  {sqlite3BeginTransaction(pParse);}

/*
** 2003 April 6
**
** 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 contains code used to implement the PRAGMA command.
**
** $Id: pragma.c,v 1.38 2004/06/09 00:48:13 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** Interpret the given string as a boolean value.
*/

    sqlite3VdbeSetColName(v, 0, "integrity_check", P3_STATIC);
    sqlite3VdbeAddOpList(v, ArraySize(initCode), initCode);

    /* Do an integrity check on each database file */
    for(i=0; i<db->nDb; i++){
      HashElem *x;
      int cnt = 0;

      sqlite3CodeVerifySchema(pParse, i);

      /* Do an integrity check of the B-Tree
      */
      for(x=sqliteHashFirst(&db->aDb[i].tblHash); x; x=sqliteHashNext(x)){
        Table *pTab = sqliteHashData(x);
        Index *pIdx;
        sqlite3VdbeAddOp(v, OP_Integer, pTab->tnum, 0);

/*
** 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 1.272 2004/06/09 00:48:13 drh Exp $
*/
#include "config.h"
#include "sqlite3.h"
#include "hash.h"
#include "parse.h"
#include <stdio.h>
#include <stdlib.h>

** work.
*/
#define NULL_DISTINCT_FOR_UNIQUE 1

/*
** The maximum number of attached databases.  This must be at least 2
** in order to support the main database file (0) and the file used to
** hold temporary tables (1).  And it must be less than 32 because
** we use a bitmask of databases with a u32 in places (for example
** the Parse.cookieMask field).
*/
#define MAX_ATTACHED 10

/*
** The next macro is used to determine where TEMP tables and indices
** are stored.  Possible values:
**

  int nSet;            /* Number of sets used so far */
  int nAgg;            /* Number of aggregate expressions */
  int nVar;            /* Number of '?' variables seen in the SQL so far */
  AggExpr *aAgg;       /* An array of aggregate expressions */
  const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
  Trigger *pNewTrigger;     /* Trigger under construct by a CREATE TRIGGER */
  TriggerStack *trigStack;  /* Trigger actions being coded */
  u32 cookieMask;      /* Bitmask of schema verified databases */
  int cookieValue[MAX_ATTACHED+2];  /* Values of cookies to verify */
  int cookieGoto;      /* Address of OP_Goto to cookie verifier subroutine */
  u32 writeMask;       /* Start a write transaction on these databases */
};

/*
** An instance of the following structure can be declared on a stack and used
** to save the Parse.zAuthContext value so that it can be restored later.
*/
struct AuthContext {

void sqlite3DebugPrintf(const char*, ...);
void sqlite3SetString(char **, const char *, ...);
void sqlite3SetNString(char **, ...);
void sqlite3ErrorMsg(Parse*, const char*, ...);
void sqlite3Dequote(char*);
int sqlite3KeywordCode(const char*, int);
int sqlite3RunParser(Parse*, const char*, char **);
void sqlite3FinishCoding(Parse*);
Expr *sqlite3Expr(int, Expr*, Expr*, Token*);
void sqlite3ExprSpan(Expr*,Token*,Token*);
Expr *sqlite3ExprFunction(ExprList*, Token*);
void sqlite3ExprDelete(Expr*);
ExprList *sqlite3ExprListAppend(ExprList*,Expr*,Token*);
void sqlite3ExprListDelete(ExprList*);
int sqlite3Init(sqlite*, char**);

  int newIdx,          /* The indice of the "new" row to access */
  int oldIdx,          /* The indice of the "old" row to access */
  int orconf,          /* ON CONFLICT policy */
  int ignoreJump       /* Instruction to jump to for RAISE(IGNORE) */
){
  Trigger * pTrigger;
  TriggerStack * pTriggerStack;


  assert(op == TK_UPDATE || op == TK_INSERT || op == TK_DELETE);
  assert(tr_tm == TK_BEFORE || tr_tm == TK_AFTER );

  assert(newIdx != -1 || oldIdx != -1);

  pTrigger = pTab->pTrigger;

      sqlite3AuthContextPop(&sContext);
      sqliteFree(pTriggerStack);

      sqlite3VdbeResolveLabel(pParse->pVdbe, endTrigger);
    }
    pTrigger = pTrigger->pNext;
  }


  return 0;
}

**
** 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 1.360 2004/06/09 00:48:14 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*

** opcode is encountered.  Depending on the ON CONFLICT setting, the
** transaction might also be rolled back if an error is encountered.
**
** P1 is the index of the database file on which the transaction is
** started.  Index 0 is the main database file and index 1 is the
** file used for temporary tables.
**
** If P2 is non-zero, then a write-transaction is started.  A RESERVED lock is
** obtained on the database file when a write-transaction is started.  No
** other process can start another write transaction while this transaction is
** underway.  Starting a write transaction also creates a rollback journal. A
** write transaction must be started before any changes can be made to the
** database.
**
** If P2 is zero, then a read-lock is obtained on the database file.
*/
case OP_Transaction: {
  int i = pOp->p1;
  Btree *pBt;

      p->apVar[n].flags = MEM_Null;
    }
  }

  sqlite3HashInit(&p->agg.hash, SQLITE_HASH_BINARY, 0);
  p->agg.pSearch = 0;
#ifdef MEMORY_DEBUG
  if( sqlite3OsFileExists("vdbe_explain") ){
    int i;
    printf("VDBE Program Listing:\n");
    for(i=0; i<p->nOp; i++){
      sqlite3VdbePrintOp(stdout, i, &p->aOp[i]);
    }
  }
  if( sqlite3OsFileExists("vdbe_trace") ){
    printf("VDBE Execution Trace:\n");
    p->trace = stdout;
  }
#endif
  p->pTos = &p->aStack[-1];
  p->pc = -1;
  p->rc = SQLITE_OK;
  p->uniqueCnt = 0;

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements.
**
** $Id: where.c,v 1.102 2004/06/09 00:48:15 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.

       pWInfo->a[0].bRev = bRev;
       *ppOrderBy = 0;
     }
  }

  /* Open all tables in the pTabList and all indices used by those tables.
  */
  sqlite3CodeVerifySchema(pParse, 1);  /* Inserts the cookie verifier Goto */
  for(i=0; i<pTabList->nSrc; i++){
    Table *pTab;
    Index *pIx;

    pTab = pTabList->a[i].pTab;
    if( pTab->isTransient || pTab->pSelect ) continue;
    sqlite3VdbeAddOp(v, OP_Integer, pTab->iDb, 0);
    sqlite3VdbeAddOp(v, OP_OpenRead, pTabList->a[i].iCursor, pTab->tnum);
    sqlite3VdbeAddOp(v, OP_SetNumColumns, pTabList->a[i].iCursor, pTab->nCol);
    if( pTab->tnum>1 ){
      sqlite3CodeVerifySchema(pParse, pTab->iDb);
    }
    if( (pIx = pWInfo->a[i].pIdx)!=0 ){
      sqlite3VdbeAddOp(v, OP_Integer, pIx->iDb, 0);
      sqlite3VdbeOp3(v, OP_OpenRead, pWInfo->a[i].iCur, pIx->tnum,
                     (char*)&pIx->keyInfo, P3_KEYINFO);
    }
  }

#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this script is testing the ATTACH and DETACH commands
# and related functionality.
#
# $Id: attach.test,v 1.23 2004/06/09 00:48:15 drh Exp $
#

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

for {set i 2} {$i<=15} {incr i} {
  file delete -force test$i.db

do_test attach-3.3 {
  catchsql {
    ATTACH DATABASE 'test2.db' AS db2;
    SELECT * FROM t2
  }
} {0 {21 x 22 y}}

# Even though 'db' has started a transaction, it should not yet have
# a lock on test2.db so 'db2' should be readable.
do_test attach-3.4 {
  execsql BEGIN
  catchsql {
    SELECT * FROM t2;
  } db2;
} {0 {21 x 22 y}}

# Reading from test2.db from db within a transaction should not
# prevent test2.db from being read by db2.
do_test attach-3.5 {
  execsql {SELECT * FROM t2}
  catchsql {
    SELECT * FROM t2;
  } db2;
} {0 {21 x 22 y}}

# Making a change to test2.db through db  causes test2.db to get
# a reserved lock.  It should still be accessible through db2.
do_test attach-3.6 {
  execsql {
    UPDATE t2 SET x=x+1 WHERE x=50;
  }
  catchsql {
    SELECT * FROM t2;
  } db2;
} {0 {21 x 22 y}}

do_test attach-3.7 {
  execsql ROLLBACK
  execsql {SELECT * FROM t2} db2
} {21 x 22 y}

# Start transactions on both db and db2.  Once again, just because
# we make a change to test2.db using db2, only a RESERVED lock is
# obtained, so test2.db should still be readable using db.
#
do_test attach-3.8 {
  execsql BEGIN
  execsql BEGIN db2
  execsql {UPDATE t2 SET x=0 WHERE 0} db2
  catchsql {SELECT * FROM t2}
} {0 {21 x 22 y}}

# It is also still accessible from db2.
do_test attach-3.9 {
  catchsql {SELECT * FROM t2} db2
} {0 {21 x 22 y}}

do_test attach-3.10 {
  execsql {SELECT * FROM t1}
} {1 2 3 4}

do_test attach-3.11 {
  catchsql {UPDATE t1 SET a=a+1}
} {0 {}}
do_test attach-3.12 {
  execsql {SELECT * FROM t1}
} {2 2 4 4}

# db2 has a RESERVED lock on test2.db, so db cannot write to any tables
# in test2.db.
do_test attach-3.13 {
  catchsql {UPDATE t2 SET x=x+1 WHERE x=50}
} {1 {database is locked}}

# Change for version 3. Transaction is no longer rolled back
# for a locked database.
execsql {ROLLBACK}

# db is able to reread its schema because db2 still only holds a
# reserved lock.
do_test attach-3.14 {


  catchsql {SELECT * FROM t1}
} {0 {1 2 3 4}}
do_test attach-3.15 {
  execsql COMMIT db2
  execsql {SELECT * FROM t1}
} {1 2 3 4}

#set btree_trace 1

# Ticket #323
do_test attach-4.1 {
  execsql {DETACH db2}
  db2 close
  sqlite db2 test2.db
  execsql {
    CREATE TABLE t3(x,y);

    CREATE TRIGGER t3r3 AFTER INSERT ON t3 BEGIN
      INSERT INTO t4 VALUES('main.' || NEW.a);
    END;
    INSERT INTO main.t3 VALUES(11,12);
    SELECT * FROM main.t4;
  }
} {main.11}

# This one is tricky.  On the UNION ALL select, we have to make sure
# the schema for both main and db2 is valid before starting to execute
# the first query of the UNION ALL.  If we wait to test the validity of
# the schema for main until after the first query has run, that test will
# fail and the query will abort but we will have already output some
# results.  When the query is retried, the results will be repeated.
#
do_test attach-4.8 {
  execsql {
    ATTACH DATABASE 'test2.db' AS db2;
    INSERT INTO db2.t3 VALUES(13,14);
    SELECT * FROM db2.t4 UNION ALL SELECT * FROM main.t4;
  }
} {db2.6 db2.13 main.11}

do_test attach-4.9 {
  execsql {
    INSERT INTO main.t3 VALUES(15,16);
    SELECT * FROM db2.t4 UNION ALL SELECT * FROM main.t4;
  }
} {db2.6 db2.13 main.11 main.15}
do_test attach-4.10 {