SQLite

**    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 1.243 2006/01/03 15:16:26 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

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

  ** more matches.  Either way, we have an error.
  */
  if( cnt!=1 ){
    char *z = 0;
    char *zErr;
    zErr = cnt==0 ? "no such column: %s" : "ambiguous column name: %s";
    if( zDb ){
      sqlite3SetString(&z, zDb, ".", zTab, ".", zCol, (char*)0);
    }else if( zTab ){
      sqlite3SetString(&z, zTab, ".", zCol, (char*)0);
    }else{
      z = sqliteStrDup(zCol);
    }
    sqlite3ErrorMsg(pParse, zErr, z);
    sqliteFree(z);
    pTopNC->nErr++;
  }

**    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 1.283 2006/01/03 15:16:26 drh Exp $
*/
#include "sqliteInt.h"


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

        sqlite3VdbeSetColName(v, i, (char*)p->span.z, p->span.n);
      }else if( fullNames || (!shortNames && pTabList->nSrc>1) ){
        char *zName = 0;
        char *zTab;
 
        zTab = pTabList->a[j].zAlias;
        if( fullNames || zTab==0 ) zTab = pTab->zName;
        sqlite3SetString(&zName, zTab, ".", zCol, (char*)0);
        sqlite3VdbeSetColName(v, i, zName, P3_DYNAMIC);
      }else{
        sqlite3VdbeSetColName(v, i, zCol, strlen(zCol));
      }
    }else if( p->span.z && p->span.z[0] ){
      sqlite3VdbeSetColName(v, i, (char*)p->span.z, p->span.n);
      /* sqlite3VdbeCompressSpace(v, addr); */

**
** 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 1.510 2006/01/03 15:16:26 drh Exp $
*/
#include "sqliteInt.h"
#include "os.h"
#include <ctype.h>
#include "vdbeInt.h"

/*

  if( db->activeVdbeCnt>1 && i && !db->autoCommit ){
    /* If this instruction implements a COMMIT or ROLLBACK, other VMs are
    ** still running, and a transaction is active, return an error indicating
    ** that the other VMs must complete first. 
    */
    sqlite3SetString(&p->zErrMsg, "cannot ", rollback?"rollback":"commit", 
        " transaction - SQL statements in progress", (char*)0);
    rc = SQLITE_ERROR;
  }else if( i!=db->autoCommit ){
    if( pOp->p2 ){
      assert( i==1 );
      sqlite3RollbackAll(db);
      db->autoCommit = 1;
    }else{

      }
    }
    return SQLITE_DONE;
  }else{
    sqlite3SetString(&p->zErrMsg,
        (!i)?"cannot start a transaction within a transaction":(
        (rollback)?"cannot rollback - no transaction is active":
                   "cannot commit - no transaction is active"), (char*)0);
         
    rc = SQLITE_ERROR;
  }
  break;
}

/* Opcode: Transaction P1 P2 *