SQLite

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that used to generate VDBE code
** that implements the ALTER TABLE command.
**
** $Id: alter.c,v 1.7 2005/06/06 21:19:57 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The code in this file only exists if we are not omitting the
** ALTER TABLE logic from the build.

    Column *pCol = &pNew->aCol[i];
    pCol->zName = sqliteStrDup(pCol->zName);
    pCol->zType = 0;
    pCol->pDflt = 0;
  }
  pNew->iDb = iDb;
  pNew->addColOffset = pTab->addColOffset;
  pNew->nRef = 1;

  /* Begin a transaction and increment the schema cookie.  */
  sqlite3BeginWriteOperation(pParse, 0, iDb);
  v = sqlite3GetVdbe(pParse);
  if( !v ) goto exit_begin_add_column;
  sqlite3ChangeCookie(pParse->db, v, iDb);

exit_begin_add_column:
  sqlite3SrcListDelete(pSrc);
  return;
}
#endif  /* SQLITE_ALTER_TABLE */

**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.325 2005/06/06 21:19:57 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.

** unlinked.
*/
void sqlite3DeleteTable(sqlite3 *db, Table *pTable){
  Index *pIndex, *pNext;
  FKey *pFKey, *pNextFKey;

  if( pTable==0 ) return;

  /* Do not delete the table until the reference count reaches zero. */
  pTable->nRef--;
  if( pTable->nRef>0 ){
    return;
  }
  assert( pTable->nRef==0 );

  /* Delete all indices associated with this table
  */
  for(pIndex = pTable->pIndex; pIndex; pIndex=pNext){
    pNext = pIndex->pNext;
    assert( pIndex->iDb==pTable->iDb || (pTable->iDb==0 && pIndex->iDb==1) );
    sqliteDeleteIndex(db, pIndex);

  }
  pTable->zName = zName;
  pTable->nCol = 0;
  pTable->aCol = 0;
  pTable->iPKey = -1;
  pTable->pIndex = 0;
  pTable->iDb = iDb;
  pTable->nRef = 1;
  if( pParse->pNewTable ) sqlite3DeleteTable(db, pParse->pNewTable);
  pParse->pNewTable = pTable;

  /* If this is the magic sqlite_sequence table used by autoincrement,
  ** then record a pointer to this table in the main database structure
  ** so that INSERT can find the table easily.
  */

  int i;
  struct SrcList_item *pItem;
  if( pList==0 ) return;
  for(pItem=pList->a, i=0; i<pList->nSrc; i++, pItem++){
    sqliteFree(pItem->zDatabase);
    sqliteFree(pItem->zName);
    sqliteFree(pItem->zAlias);

    sqlite3DeleteTable(0, pItem->pTab);

    sqlite3SelectDelete(pItem->pSelect);
    sqlite3ExprDelete(pItem->pOn);
    sqlite3IdListDelete(pItem->pUsing);
  }
  sqliteFree(pList);
}

**    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 1.105 2005/06/06 21:19:57 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.
*/
Table *sqlite3SrcListLookup(Parse *pParse, SrcList *pSrc){
  Table *pTab = 0;
  int i;
  struct SrcList_item *pItem;
  for(i=0, pItem=pSrc->a; i<pSrc->nSrc; i++, pItem++){
    pTab = sqlite3LocateTable(pParse, pItem->zName, pItem->zDatabase);
    sqlite3DeleteTable(pParse->db, pItem->pTab);
    pItem->pTab = pTab;
    if( pTab ){
      pTab->nRef++;
    }
  }
  return pTab;
}

/*
** Check to make sure the given table is writable.  If it is not
** writable, generate an error message and return 1.  If it is

**    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 1.205 2005/06/06 21:19:57 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

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

  nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
  pNew = sqliteMallocRaw( nByte );
  if( pNew==0 ) return 0;
  pNew->nSrc = pNew->nAlloc = p->nSrc;
  for(i=0; i<p->nSrc; i++){
    struct SrcList_item *pNewItem = &pNew->a[i];
    struct SrcList_item *pOldItem = &p->a[i];
    Table *pTab;
    pNewItem->zDatabase = sqliteStrDup(pOldItem->zDatabase);
    pNewItem->zName = sqliteStrDup(pOldItem->zName);
    pNewItem->zAlias = sqliteStrDup(pOldItem->zAlias);
    pNewItem->jointype = pOldItem->jointype;
    pNewItem->iCursor = pOldItem->iCursor;
    pTab = pNewItem->pTab = pOldItem->pTab;
    if( pTab ){
      pTab->nRef++;
    }
    pNewItem->pSelect = sqlite3SelectDup(pOldItem->pSelect);
    pNewItem->pOn = sqlite3ExprDup(pOldItem->pOn);
    pNewItem->pUsing = sqlite3IdListDup(pOldItem->pUsing);
    pNewItem->colUsed = pOldItem->colUsed;
  }
  return pNew;

**    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 1.250 2005/06/06 21:19:57 drh Exp $
*/
#include "sqliteInt.h"


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

  if( sqlite3SelectResolve(pParse, pSelect, 0) ){
    return 0;
  }
  pTab = sqliteMalloc( sizeof(Table) );
  if( pTab==0 ){
    return 0;
  }
  pTab->nRef = 1;
  pTab->zName = zTabName ? sqliteStrDup(zTabName) : 0;
  pEList = pSelect->pEList;
  pTab->nCol = pEList->nExpr;
  assert( pTab->nCol>0 );
  pTab->aCol = aCol = sqliteMalloc( sizeof(pTab->aCol[0])*pTab->nCol );
  for(i=0, pCol=aCol; i<pTab->nCol; i++, pCol++){
    Expr *p, *pR;

#ifndef SQLITE_OMIT_SUBQUERY
      /* A sub-query in the FROM clause of a SELECT */
      assert( pFrom->pSelect!=0 );
      if( pFrom->zAlias==0 ){
        pFrom->zAlias =
          sqlite3MPrintf("sqlite_subquery_%p_", (void*)pFrom->pSelect);
      }
      assert( pFrom->pTab==0 );
      pFrom->pTab = pTab = 
        sqlite3ResultSetOfSelect(pParse, pFrom->zAlias, pFrom->pSelect);
      if( pTab==0 ){
        return 1;
      }
      /* The isTransient flag indicates that the Table structure has been
      ** dynamically allocated and may be freed at any time.  In other words,
      ** pTab is not pointing to a persistent table structure that defines
      ** part of the schema. */
      pTab->isTransient = 1;
#endif
    }else{
      /* An ordinary table or view name in the FROM clause */
      assert( pFrom->pTab==0 );
      pFrom->pTab = pTab = 
        sqlite3LocateTable(pParse,pFrom->zName,pFrom->zDatabase);
      if( pTab==0 ){
        return 1;
      }
      pTab->nRef++;
#ifndef SQLITE_OMIT_VIEW
      if( pTab->pSelect ){
        /* We reach here if the named table is a really a view */
        if( sqlite3ViewGetColumnNames(pParse, pTab) ){
          return 1;
        }
        /* If pFrom->pSelect!=0 it means we are dealing with a

    }
    sqlite3ExprListDelete(pEList);
    p->pEList = pNew;
  }
  return rc;
}



































#ifndef SQLITE_OMIT_COMPOUND_SELECT
/*
** This routine associates entries in an ORDER BY expression list with
** columns in a result.  For each ORDER BY expression, the opcode of
** the top-level node is changed to TK_COLUMN and the iColumn value of
** the top-level node is filled in with column number and the iTable
** value of the top-level node is filled with iTable parameter.

  ** those references with expressions that resolve to the subquery FROM
  ** elements we are now copying in.
  */
  iParent = pSubitem->iCursor;
  {
    int nSubSrc = pSubSrc->nSrc;
    int jointype = pSubitem->jointype;



    sqlite3DeleteTable(0, pSubitem->pTab);

    sqliteFree(pSubitem->zDatabase);
    sqliteFree(pSubitem->zName);
    sqliteFree(pSubitem->zAlias);
    if( nSubSrc>1 ){
      int extra = nSubSrc - 1;
      for(i=1; i<nSubSrc; i++){
        pSrc = sqlite3SrcListAppend(pSrc, 0, 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 1.386 2005/06/06 21:19:57 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

  Select *pSelect; /* NULL for tables.  Points to definition if a view. */
  u8 readOnly;     /* True if this table should not be written by the user */
  u8 iDb;          /* Index into sqlite.aDb[] of the backend for this table */
  u8 isTransient;  /* True if automatically deleted when VDBE finishes */
  u8 hasPrimKey;   /* True if there exists a primary key */
  u8 keyConf;      /* What to do in case of uniqueness conflict on iPKey */
  u8 autoInc;      /* True if the integer primary key is autoincrement */
  int nRef;          /* Number of pointers to this Table */
  Trigger *pTrigger; /* List of SQL triggers on this table */
  FKey *pFKey;       /* Linked list of all foreign keys in this table */
  char *zColAff;     /* String defining the affinity of each column */
#ifndef SQLITE_OMIT_ALTERTABLE
  int addColOffset;  /* Offset in CREATE TABLE statement to add a new column */
#endif
};

#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# This file implements tests for miscellanous features that were
# left out of other test files.
#
# $Id: misc5.test,v 1.3 2005/06/06 21:19:58 drh Exp $

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

# Build records using the MakeRecord opcode such that the size of the 
# header is at the transition point in the size of a varint.
#

2305843009213693951\
2305843009213693952\
2305843009213693953\
4611686018427387903\
4611686018427387904\
4611686018427387905"

# Ticket #1210.  Do proper reference counting of Table structures
# so that deeply nested SELECT statements can be flattened correctly.
#
do_test misc5-3.1 {
  execsql {
    CREATE TABLE songs(songid, artist, timesplayed);
    INSERT INTO songs VALUES(1,'one',1);
    INSERT INTO songs VALUES(2,'one',2);
    INSERT INTO songs VALUES(3,'two',3);
    INSERT INTO songs VALUES(4,'three',5);
    INSERT INTO songs VALUES(5,'one',7);
    INSERT INTO songs VALUES(6,'two',11);
    SELECT DISTINCT artist 
    FROM (    
     SELECT DISTINCT artist    
     FROM songs      
     WHERE songid IN (    
      SELECT songid    
      FROM songs    
      WHERE LOWER(artist) = (    
        SELECT DISTINCT LOWER(artist)    
        FROM (      
          SELECT DISTINCT artist,sum(timesplayed) AS total      
          FROM songs      
          GROUP BY LOWER(artist)      
          ORDER BY total DESC      
          LIMIT 10    
        )    
        WHERE artist <> '' 
      )  
     )       
    )  
    ORDER BY LOWER(artist) ASC;
  }
} {two}


finish_test