SQLite

**     CREATE INDEX
**     DROP INDEX
**     creating ID lists
**     BEGIN TRANSACTION
**     COMMIT
**     ROLLBACK
**
** $Id: build.c,v 1.294 2005/01/18 14:45:48 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.

#ifndef SQLITE_OMIT_VIEW
/*
** The Table structure pTable is really a VIEW.  Fill in the names of
** the columns of the view in the pTable structure.  Return the number
** of errors.  If an error is seen leave an error message in pParse->zErrMsg.
*/
int sqlite3ViewGetColumnNames(Parse *pParse, Table *pTable){
  Table *pSelTab;   /* A fake table from which we get the result set */
  Select *pSel;     /* Copy of the SELECT that implements the view */

  int nErr = 0;     /* Number of errors encountered */
  int n;            /* Temporarily holds the number of cursors assigned */

  assert( pTable );

  /* A positive nCol means the columns names for this view are
  ** already known.
  */
  if( pTable->nCol>0 ) return 0;

  */
  if( pTable->nCol<0 ){
    sqlite3ErrorMsg(pParse, "view %s is circularly defined", pTable->zName);
    return 1;
  }

  /* If we get this far, it means we need to compute the table names.




  ** Note that the call to sqlite3ResultSetOfSelect() will expand any
  ** "*" elements in the results set of the view and will assign cursors

  ** to the elements of the FROM clause.  But we do not want these changes
  ** to be permanent.  So the computation is done on a copy of the SELECT
  ** statement that defines the view.
  */
  assert( pTable->pSelect );
  pSel = sqlite3SelectDup(pTable->pSelect);
  n = pParse->nTab;
  sqlite3SrcListAssignCursors(pParse, pSel->pSrc);


  pTable->nCol = -1;
  pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSel);
  pParse->nTab = n;
  if( pSelTab ){
    assert( pTable->aCol==0 );
    pTable->nCol = pSelTab->nCol;
    pTable->aCol = pSelTab->aCol;
    pSelTab->nCol = 0;
    pSelTab->aCol = 0;
    sqlite3DeleteTable(0, pSelTab);
    DbSetProperty(pParse->db, pTable->iDb, DB_UnresetViews);
  }else{
    pTable->nCol = 0;
    nErr++;
  }
  sqlite3SelectDelete(pSel);


  return nErr;  
}
#endif /* SQLITE_OMIT_VIEW */

#ifndef SQLITE_OMIT_VIEW
/*
** Clear the column names from every VIEW in database idx.

}

/*
** Assign cursors to all tables in a SrcList
*/
void sqlite3SrcListAssignCursors(Parse *pParse, SrcList *pList){
  int i;
  struct SrcList_item *pItem;
  for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
    if( pItem->iCursor>=0 ) break;
    pItem->iCursor = pParse->nTab++;
    if( pItem->pSelect ){
      sqlite3SrcListAssignCursors(pParse, pItem->pSelect->pSrc);
    }
  }
}

/*
** Add an alias to the last identifier on the given identifier list.
*/

**    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 1.225 2005/01/18 14:45:48 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, 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;

  }
  return z;
}

/*
** Forward declaration
*/
static int prepSelectStmt(Parse*, Select*);

/*
** Given a SELECT statement, generate a Table structure that describes
** the result set of that SELECT.
*/
Table *sqlite3ResultSetOfSelect(Parse *pParse, char *zTabName, Select *pSelect){
  Table *pTab;
  int i, j;
  ExprList *pEList;
  Column *aCol, *pCol;

  if( prepSelectStmt(pParse, pSelect) ){
    return 0;
  }
  pTab = sqliteMalloc( sizeof(Table) );
  if( pTab==0 ){
    return 0;
  }
  pTab->zName = zTabName ? sqliteStrDup(zTabName) : 0;

    }
  }
  pTab->iPKey = -1;
  return pTab;
}

/*
** Prepare a SELECT statement for processing by doing the following
** things:
**
**    (1)  Make sure VDBE cursor numbers have been assigned to every
**         element of the FROM clause.
**
**    (2)  Fill in the pTabList->a[].pTab fields in the SrcList that 
**         defines FROM clause.  When views appear in the FROM clause,
**         fill pTabList->a[].pSelect with a copy of the SELECT statement
**         that implements the view.  A copy is made of the view's SELECT
**         statement so that we can freely modify or delete that statement
**         without worrying about messing up the presistent representation
**         of the view.
**
**    (3)  Add terms to the WHERE clause to accomodate the NATURAL keyword
**         on joins and the ON and USING clause of joins.
**
**    (4)  Scan the list of columns in the result set (pEList) looking
**         for instances of the "*" operator or the TABLE.* operator.
**         If found, expand each "*" to be every column in every table
**         and TABLE.* to be every column in TABLE.
**
** Return 0 on success.  If there are problems, leave an error message
** in pParse and return non-zero.
*/
static int prepSelectStmt(Parse *pParse, Select *p){
  int i, j, k, rc;
  SrcList *pTabList;
  ExprList *pEList;
  Table *pTab;
  struct SrcList_item *pFrom;

  if( p==0 || p->pSrc==0 ) return 1;
  pTabList = p->pSrc;
  pEList = p->pEList;

  /* Make sure cursor numbers have been assigned to all entries in
  ** the FROM clause of the SELECT statement.
  */
  sqlite3SrcListAssignCursors(pParse, p->pSrc);

  /* Look up every table named in the FROM clause of the select.  If
  ** an entry of the FROM clause is a subquery instead of a table or view,
  ** then create a transient table structure to describe the subquery.
  */
  for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
    if( pFrom->pTab!=0 ){
      /* This statement has already been prepared.  There is no need
      ** to go further. */
      assert( i==0 );
      return 0;
    }
    if( pFrom->zName==0 ){
      /* A sub-query in the FROM clause of a SELECT */
      assert( pFrom->pSelect!=0 );
      if( pFrom->zAlias==0 ){
        pFrom->zAlias =

  int i, j;
  ExprList *pEList;

  if( pSelect==0 || pOrderBy==0 ) return 1;
  if( mustComplete ){
    for(i=0; i<pOrderBy->nExpr; i++){ pOrderBy->a[i].done = 0; }
  }
  if( prepSelectStmt(pParse, pSelect) ){
    return 1;
  }
  if( pSelect->pPrior ){
    if( matchOrderbyToColumn(pParse, pSelect->pPrior, pOrderBy, iTable, 0) ){
      return 1;
    }
  }

  KeyInfo *pKeyInfo;
  int nColumn;
  sqlite3 *db = pParse->db;
  int i;
  Vdbe *v = pParse->pVdbe;
  int addr;

  if( prepSelectStmt(pParse, p) ){
    return 0;
  }
  nColumn = p->pEList->nExpr;
  pKeyInfo = sqliteMalloc( sizeof(*pKeyInfo)+nColumn*sizeof(CollSeq*) );
  if( pKeyInfo==0 ) return 0;
  pKeyInfo->enc = db->enc;
  pKeyInfo->nField = nColumn;

  pTabList = p->pSrc;
  pWhere = p->pWhere;
  pOrderBy = p->pOrderBy;
  pGroupBy = p->pGroupBy;
  pHaving = p->pHaving;
  isDistinct = p->isDistinct;





  /* 
  ** Do not even attempt to generate any code if we have already seen
  ** errors before this routine starts.
  */
  if( pParse->nErr>0 ) goto select_end;





  if( prepSelectStmt(pParse, p) ){
    goto select_end;
  }
  pWhere = p->pWhere;
  pEList = p->pEList;
  if( pEList==0 ) goto select_end;

  /* If writing to memory or generating a set

/*
** 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 1.356 2005/01/18 14:45:48 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

** offset).  But later on, nLimit and nOffset become the memory locations
** in the VDBE that record the limit and offset counters.
*/
struct Select {
  ExprList *pEList;      /* The fields of the result */
  u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
  u8 isDistinct;         /* True if the DISTINCT keyword is present */


  SrcList *pSrc;         /* The FROM clause */
  Expr *pWhere;          /* The WHERE clause */
  ExprList *pGroupBy;    /* The GROUP BY clause */
  Expr *pHaving;         /* The HAVING clause */
  ExprList *pOrderBy;    /* The ORDER BY clause */
  Select *pPrior;        /* Prior select in a compound select statement */
  int nLimit, nOffset;   /* LIMIT and OFFSET values.  -1 means not used */

#
#***********************************************************************
# This file implements regression tests for SQLite library.
#
# This file implements tests for miscellanous features that were
# left out of other test files.
#
# $Id: misc4.test,v 1.10 2005/01/18 14:45:49 drh Exp $

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

# Prepare a statement that will create a temporary table.  Then do
# a rollback.  Then try to execute the prepared statement.
#

    INSERT INTO Table2 VALUES (1, 'a');
    SELECT ID, Value FROM Table1
       UNION SELECT ID, max(Value) FROM Table2 GROUP BY 1,2
    ORDER BY 1, 2;
  }
} {{} {} 1 x 1 z}
} ;# ifcapable compound

# Ticket #1047.  Make sure column types are preserved in subqueries.
#
do_test misc4-4.1 {
  execsql {
    create table a(key varchar, data varchar);
    create table b(key varchar, period integer);
    insert into a values('01','data01');
    insert into a values('+1','data+1');
    
    insert into b values ('01',1);
    insert into b values ('01',2);
    insert into b values ('+1',3);
    insert into b values ('+1',4);
    
    select a.*, x.*
      from a, (select key,sum(period) from b group by key) as x
      where a.key=x.key;
  }
} {01 data01 01 3.0 +1 data+1 +1 7.0}

finish_test