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Overview
Comment:Correctly handle an ORDER BY clause on an outer query when applying the compound-subquery flattening optimization. Ticket [d11a6e908f]. Also add the SQLITE_ENABLE_SELECTTRACE option for additional debugging and analysis information about select statement processing.
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Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: d5880abd63c83c88e135257373afa0a3fd88297e
User & Date: drh 2014-09-21 22:31:52
Original Comment: Correctly handle an ORDER BY clause on an outer query when applying the compound-subquery flattening optimization. Ticket [89398880bcfff]. Also add the SQLITE_ENABLE_SELECTTRACE option for additional debugging and analysis information about select statement processing.
Context
2014-09-22
03:22
Disable shared memory operations using the unix-nolock VFS. check-in: 10a6e510 user: drh tags: trunk
2014-09-21
23:08
Merge in all recent changes from trunk. check-in: 3967ebe8 user: drh tags: apple-osx
22:49
Merge all recent trunk changes into the sessions branch. check-in: 6406b77f user: drh tags: sessions
22:31
Correctly handle an ORDER BY clause on an outer query when applying the compound-subquery flattening optimization. Ticket [d11a6e908f]. Also add the SQLITE_ENABLE_SELECTTRACE option for additional debugging and analysis information about select statement processing. check-in: d5880abd user: drh tags: trunk
20:31
Add test cases for ticket [d11a6e908f]. Closed-Leaf check-in: 9683e001 user: drh tags: select-trace
2014-09-20
00:35
Fix the usage of the _GNU_SOURCE and _BSD_SOURCE macros in the main internal header file, sqliteInt.h. Set HAVE_STRCHRNUL to 1 by default on Linux only. check-in: 59e2c9df user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Added ext/misc/showauth.c.















































































































































































































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/*
** 2014-09-21
**
** 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 SQLite extension adds a debug "authorizer" callback to the database
** connection.  The callback merely writes the authorization request to
** standard output and returns SQLITE_OK.
**
** This extension can be used (for example) in the command-line shell to
** trace the operation of the authorizer.
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <stdio.h>

/*
** Display the authorization request
*/
static int authCallback(
  void *pClientData,
  int op,
  const char *z1,
  const char *z2,
  const char *z3,
  const char *z4
){
  const char *zOp;
  char zOpSpace[50];
  switch( op ){
    case SQLITE_CREATE_INDEX:        zOp = "CREATE_INDEX";        break;
    case SQLITE_CREATE_TABLE:        zOp = "CREATE_TABLE";        break;
    case SQLITE_CREATE_TEMP_INDEX:   zOp = "CREATE_TEMP_INDEX";   break;
    case SQLITE_CREATE_TEMP_TABLE:   zOp = "CREATE_TEMP_TABLE";   break;
    case SQLITE_CREATE_TEMP_TRIGGER: zOp = "CREATE_TEMP_TRIGGER"; break;
    case SQLITE_CREATE_TEMP_VIEW:    zOp = "CREATE_TEMP_VIEW";    break;
    case SQLITE_CREATE_TRIGGER:      zOp = "CREATE_TRIGGER";      break;
    case SQLITE_CREATE_VIEW:         zOp = "CREATE_VIEW";         break;
    case SQLITE_DELETE:              zOp = "DELETE";              break;
    case SQLITE_DROP_INDEX:          zOp = "DROP_INDEX";          break;
    case SQLITE_DROP_TABLE:          zOp = "DROP_TABLE";          break;
    case SQLITE_DROP_TEMP_INDEX:     zOp = "DROP_TEMP_INDEX";     break;
    case SQLITE_DROP_TEMP_TABLE:     zOp = "DROP_TEMP_TABLE";     break;
    case SQLITE_DROP_TEMP_TRIGGER:   zOp = "DROP_TEMP_TRIGGER";   break;
    case SQLITE_DROP_TEMP_VIEW:      zOp = "DROP_TEMP_VIEW";      break;
    case SQLITE_DROP_TRIGGER:        zOp = "DROP_TRIGGER";        break;
    case SQLITE_DROP_VIEW:           zOp = "DROP_VIEW";           break;
    case SQLITE_INSERT:              zOp = "INSERT";              break;
    case SQLITE_PRAGMA:              zOp = "PRAGMA";              break;
    case SQLITE_READ:                zOp = "READ";                break;
    case SQLITE_SELECT:              zOp = "SELECT";              break;
    case SQLITE_TRANSACTION:         zOp = "TRANSACTION";         break;
    case SQLITE_UPDATE:              zOp = "UPDATE";              break;
    case SQLITE_ATTACH:              zOp = "ATTACH";              break;
    case SQLITE_DETACH:              zOp = "DETACH";              break;
    case SQLITE_ALTER_TABLE:         zOp = "ALTER_TABLE";         break;
    case SQLITE_REINDEX:             zOp = "REINDEX";             break;
    case SQLITE_ANALYZE:             zOp = "ANALYZE";             break;
    case SQLITE_CREATE_VTABLE:       zOp = "CREATE_VTABLE";       break;
    case SQLITE_DROP_VTABLE:         zOp = "DROP_VTABLE";         break;
    case SQLITE_FUNCTION:            zOp = "FUNCTION";            break;
    case SQLITE_SAVEPOINT:           zOp = "SAVEPOINT";           break;
    case SQLITE_COPY:                zOp = "COPY";                break;
    case SQLITE_RECURSIVE:           zOp = "RECURSIVE";           break;


    default: {
      sqlite3_snprintf(sizeof(zOpSpace), zOpSpace, "%d", op);
      zOp = zOpSpace;
      break;
    }
  }
  if( z1==0 ) z1 = "NULL";
  if( z2==0 ) z2 = "NULL";
  if( z3==0 ) z3 = "NULL";
  if( z4==0 ) z4 = "NULL";
  printf("AUTH: %s,%s,%s,%s,%s\n", zOp, z1, z2, z3, z4);
  return SQLITE_OK;
}



#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_showauth_init(
  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  int rc = SQLITE_OK;
  SQLITE_EXTENSION_INIT2(pApi);
  (void)pzErrMsg;  /* Unused parameter */
  rc = sqlite3_set_authorizer(db, authCallback, 0);
  return rc;
}

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  pNew->iLimit = 0;
  pNew->iOffset = 0;
  pNew->selFlags = p->selFlags & ~SF_UsesEphemeral;
  pNew->addrOpenEphm[0] = -1;
  pNew->addrOpenEphm[1] = -1;
  pNew->nSelectRow = p->nSelectRow;
  pNew->pWith = withDup(db, p->pWith);

  return pNew;
}
#else
Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){
  assert( p==0 );
  return 0;
}







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  pNew->iLimit = 0;
  pNew->iOffset = 0;
  pNew->selFlags = p->selFlags & ~SF_UsesEphemeral;
  pNew->addrOpenEphm[0] = -1;
  pNew->addrOpenEphm[1] = -1;
  pNew->nSelectRow = p->nSelectRow;
  pNew->pWith = withDup(db, p->pWith);
  sqlite3SelectSetName(pNew, p->zSelName);
  return pNew;
}
#else
Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){
  assert( p==0 );
  return 0;
}

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  A = pRhs;
}
%type multiselect_op {int}
multiselect_op(A) ::= UNION(OP).             {A = @OP;}
multiselect_op(A) ::= UNION ALL.             {A = TK_ALL;}
multiselect_op(A) ::= EXCEPT|INTERSECT(OP).  {A = @OP;}
%endif SQLITE_OMIT_COMPOUND_SELECT
oneselect(A) ::= SELECT distinct(D) selcollist(W) from(X) where_opt(Y)
                 groupby_opt(P) having_opt(Q) orderby_opt(Z) limit_opt(L). {
  A = sqlite3SelectNew(pParse,W,X,Y,P,Q,Z,D,L.pLimit,L.pOffset);
























}
oneselect(A) ::= values(X).    {A = X;}

%type values {Select*}
%destructor values {sqlite3SelectDelete(pParse->db, $$);}
values(A) ::= VALUES LP nexprlist(X) RP. {
  A = sqlite3SelectNew(pParse,X,0,0,0,0,0,SF_Values,0,0);







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  A = pRhs;
}
%type multiselect_op {int}
multiselect_op(A) ::= UNION(OP).             {A = @OP;}
multiselect_op(A) ::= UNION ALL.             {A = TK_ALL;}
multiselect_op(A) ::= EXCEPT|INTERSECT(OP).  {A = @OP;}
%endif SQLITE_OMIT_COMPOUND_SELECT
oneselect(A) ::= SELECT(S) distinct(D) selcollist(W) from(X) where_opt(Y)
                 groupby_opt(P) having_opt(Q) orderby_opt(Z) limit_opt(L). {
  A = sqlite3SelectNew(pParse,W,X,Y,P,Q,Z,D,L.pLimit,L.pOffset);
#if SELECTTRACE_ENABLED
  /* Populate the Select.zSelName[] string that is used to help with
  ** query planner debugging, to differentiate between multiple Select
  ** objects in a complex query.
  **
  ** If the SELECT keyword is immediately followed by a C-style comment
  ** then extract the first few alphanumeric characters from within that
  ** comment to be the zSelName value.  Otherwise, the label is #N where
  ** is an integer that is incremented with each SELECT statement seen.
  */
  if( A!=0 ){
    const char *z = S.z+6;
    int i;
    sqlite3_snprintf(sizeof(A->zSelName), A->zSelName, "#%d",
                     ++pParse->nSelect);
    while( z[0]==' ' ) z++;
    if( z[0]=='/' && z[1]=='*' ){
      z += 2;
      while( z[0]==' ' ) z++;
      for(i=0; sqlite3Isalnum(z[i]); i++){}
      sqlite3_snprintf(sizeof(A->zSelName), A->zSelName, "%.*s", i, z);
    }
  }
#endif /* SELECTRACE_ENABLED */
}
oneselect(A) ::= values(X).    {A = X;}

%type values {Select*}
%destructor values {sqlite3SelectDelete(pParse->db, $$);}
values(A) ::= VALUES LP nexprlist(X) RP. {
  A = sqlite3SelectNew(pParse,X,0,0,0,0,0,SF_Values,0,0);

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**    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.
*/
#include "sqliteInt.h"















/*
** An instance of the following object is used to record information about
** how to process the DISTINCT keyword, to simplify passing that information
** into the selectInnerLoop() routine.
*/
typedef struct DistinctCtx DistinctCtx;
................................................................................
    pNew = 0;
  }else{
    assert( pNew->pSrc!=0 || pParse->nErr>0 );
  }
  assert( pNew!=&standin );
  return pNew;
}













/*
** Delete the given Select structure and all of its substructures.
*/
void sqlite3SelectDelete(sqlite3 *db, Select *p){
  if( p ){
    clearSelect(db, p);
................................................................................
      for(ii=0; ii<p->pOrderBy->nExpr; ii++){
        if( p->pOrderBy->a[ii].u.x.iOrderByCol==0 ) return 0;
      }
    }
  }

  /***** If we reach this point, flattening is permitted. *****/



  /* Authorize the subquery */
  pParse->zAuthContext = pSubitem->zName;
  TESTONLY(i =) sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0);
  testcase( i==SQLITE_DENY );
  pParse->zAuthContext = zSavedAuthContext;

................................................................................
    Select *pPrior = p->pPrior;
    p->pOrderBy = 0;
    p->pSrc = 0;
    p->pPrior = 0;
    p->pLimit = 0;
    p->pOffset = 0;
    pNew = sqlite3SelectDup(db, p, 0);

    p->pOffset = pOffset;
    p->pLimit = pLimit;
    p->pOrderBy = pOrderBy;
    p->pSrc = pSrc;
    p->op = TK_ALL;
    if( pNew==0 ){
      p->pPrior = pPrior;
    }else{
      pNew->pPrior = pPrior;
      if( pPrior ) pPrior->pNext = pNew;
      pNew->pNext = p;
      p->pPrior = pNew;



    }
    if( db->mallocFailed ) return 1;
  }

  /* Begin flattening the iFrom-th entry of the FROM clause 
  ** in the outer query.
  */
................................................................................
    }
    substExprList(db, pParent->pEList, iParent, pSub->pEList);
    if( isAgg ){
      substExprList(db, pParent->pGroupBy, iParent, pSub->pEList);
      pParent->pHaving = substExpr(db, pParent->pHaving, iParent, pSub->pEList);
    }
    if( pSub->pOrderBy ){














      assert( pParent->pOrderBy==0 );

      pParent->pOrderBy = pSub->pOrderBy;
      pSub->pOrderBy = 0;
    }else if( pParent->pOrderBy ){
      substExprList(db, pParent->pOrderBy, iParent, pSub->pEList);
    }
    if( pSub->pWhere ){
      pWhere = sqlite3ExprDup(db, pSub->pWhere, 0);
    }else{
................................................................................
      pTab->nRef++;
#if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE)
      if( pTab->pSelect || IsVirtual(pTab) ){
        /* We reach here if the named table is a really a view */
        if( sqlite3ViewGetColumnNames(pParse, pTab) ) return WRC_Abort;
        assert( pFrom->pSelect==0 );
        pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect, 0);

        sqlite3WalkSelect(pWalker, pFrom->pSelect);
      }
#endif
    }

    /* Locate the index named by the INDEXED BY clause, if any. */
    if( sqlite3IndexedByLookup(pParse, pFrom) ){
................................................................................

  db = pParse->db;
  if( p==0 || db->mallocFailed || pParse->nErr ){
    return 1;
  }
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;
  memset(&sAggInfo, 0, sizeof(sAggInfo));





  assert( p->pOrderBy==0 || pDest->eDest!=SRT_DistFifo );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_Fifo );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_DistQueue );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_Queue );
  if( IgnorableOrderby(pDest) ){
    assert(pDest->eDest==SRT_Exists || pDest->eDest==SRT_Union || 
................................................................................

#ifndef SQLITE_OMIT_COMPOUND_SELECT
  /* If there is are a sequence of queries, do the earlier ones first.
  */
  if( p->pPrior ){
    rc = multiSelect(pParse, p, pDest);
    explainSetInteger(pParse->iSelectId, iRestoreSelectId);




    return rc;
  }
#endif

  /* If the query is DISTINCT with an ORDER BY but is not an aggregate, and 
  ** if the select-list is the same as the ORDER BY list, then this query
  ** can be rewritten as a GROUP BY. In other words, this:
................................................................................
  */
  if( rc==SQLITE_OK && pDest->eDest==SRT_Output ){
    generateColumnNames(pParse, pTabList, pEList);
  }

  sqlite3DbFree(db, sAggInfo.aCol);
  sqlite3DbFree(db, sAggInfo.aFunc);




  return rc;
}

#if defined(SQLITE_ENABLE_TREE_EXPLAIN)
/*
** Generate a human-readable description of a the Select object.
*/







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**    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.
*/
#include "sqliteInt.h"

/*
** Trace output macros
*/
#if SELECTTRACE_ENABLED
/***/ int sqlite3SelectTrace = 0;
# define SELECTTRACE(K,P,S,X)  \
  if(sqlite3SelectTrace&(K))   \
    sqlite3DebugPrintf("%*s%s.%p: ",(P)->nSelectIndent*2-2,"",(S)->zSelName,(S)),\
    sqlite3DebugPrintf X
#else
# define SELECTTRACE(K,P,S,X)
#endif


/*
** An instance of the following object is used to record information about
** how to process the DISTINCT keyword, to simplify passing that information
** into the selectInnerLoop() routine.
*/
typedef struct DistinctCtx DistinctCtx;
................................................................................
    pNew = 0;
  }else{
    assert( pNew->pSrc!=0 || pParse->nErr>0 );
  }
  assert( pNew!=&standin );
  return pNew;
}

#if SELECTTRACE_ENABLED
/*
** Set the name of a Select object
*/
void sqlite3SelectSetName(Select *p, const char *zName){
  if( p && zName ){
    sqlite3_snprintf(sizeof(p->zSelName), p->zSelName, "%s", zName);
  }
}
#endif


/*
** Delete the given Select structure and all of its substructures.
*/
void sqlite3SelectDelete(sqlite3 *db, Select *p){
  if( p ){
    clearSelect(db, p);
................................................................................
      for(ii=0; ii<p->pOrderBy->nExpr; ii++){
        if( p->pOrderBy->a[ii].u.x.iOrderByCol==0 ) return 0;
      }
    }
  }

  /***** If we reach this point, flattening is permitted. *****/
  SELECTTRACE(1,pParse,p,("flatten %s.%p from term %d\n",
                   pSub->zSelName, pSub, iFrom));

  /* Authorize the subquery */
  pParse->zAuthContext = pSubitem->zName;
  TESTONLY(i =) sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0);
  testcase( i==SQLITE_DENY );
  pParse->zAuthContext = zSavedAuthContext;

................................................................................
    Select *pPrior = p->pPrior;
    p->pOrderBy = 0;
    p->pSrc = 0;
    p->pPrior = 0;
    p->pLimit = 0;
    p->pOffset = 0;
    pNew = sqlite3SelectDup(db, p, 0);
    sqlite3SelectSetName(pNew, pSub->zSelName);
    p->pOffset = pOffset;
    p->pLimit = pLimit;
    p->pOrderBy = pOrderBy;
    p->pSrc = pSrc;
    p->op = TK_ALL;
    if( pNew==0 ){
      p->pPrior = pPrior;
    }else{
      pNew->pPrior = pPrior;
      if( pPrior ) pPrior->pNext = pNew;
      pNew->pNext = p;
      p->pPrior = pNew;
      SELECTTRACE(2,pParse,p,
         ("compound-subquery flattener creates %s.%p as peer\n",
         pNew->zSelName, pNew));
    }
    if( db->mallocFailed ) return 1;
  }

  /* Begin flattening the iFrom-th entry of the FROM clause 
  ** in the outer query.
  */
................................................................................
    }
    substExprList(db, pParent->pEList, iParent, pSub->pEList);
    if( isAgg ){
      substExprList(db, pParent->pGroupBy, iParent, pSub->pEList);
      pParent->pHaving = substExpr(db, pParent->pHaving, iParent, pSub->pEList);
    }
    if( pSub->pOrderBy ){
      /* At this point, any non-zero iOrderByCol values indicate that the
      ** ORDER BY column expression is identical to the iOrderByCol'th
      ** expression returned by SELECT statement pSub. Since these values
      ** do not necessarily correspond to columns in SELECT statement pParent,
      ** zero them before transfering the ORDER BY clause.
      **
      ** Not doing this may cause an error if a subsequent call to this
      ** function attempts to flatten a compound sub-query into pParent
      ** (the only way this can happen is if the compound sub-query is
      ** currently part of pSub->pSrc). See ticket [d11a6e908f].  */
      ExprList *pOrderBy = pSub->pOrderBy;
      for(i=0; i<pOrderBy->nExpr; i++){
        pOrderBy->a[i].u.x.iOrderByCol = 0;
      }
      assert( pParent->pOrderBy==0 );
      assert( pSub->pPrior==0 );
      pParent->pOrderBy = pOrderBy;
      pSub->pOrderBy = 0;
    }else if( pParent->pOrderBy ){
      substExprList(db, pParent->pOrderBy, iParent, pSub->pEList);
    }
    if( pSub->pWhere ){
      pWhere = sqlite3ExprDup(db, pSub->pWhere, 0);
    }else{
................................................................................
      pTab->nRef++;
#if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE)
      if( pTab->pSelect || IsVirtual(pTab) ){
        /* We reach here if the named table is a really a view */
        if( sqlite3ViewGetColumnNames(pParse, pTab) ) return WRC_Abort;
        assert( pFrom->pSelect==0 );
        pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect, 0);
        sqlite3SelectSetName(pFrom->pSelect, pTab->zName);
        sqlite3WalkSelect(pWalker, pFrom->pSelect);
      }
#endif
    }

    /* Locate the index named by the INDEXED BY clause, if any. */
    if( sqlite3IndexedByLookup(pParse, pFrom) ){
................................................................................

  db = pParse->db;
  if( p==0 || db->mallocFailed || pParse->nErr ){
    return 1;
  }
  if( sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0) ) return 1;
  memset(&sAggInfo, 0, sizeof(sAggInfo));
#if SELECTTRACE_ENABLED
  pParse->nSelectIndent++;
  SELECTTRACE(1,pParse,p, ("begin processing\n"));
#endif

  assert( p->pOrderBy==0 || pDest->eDest!=SRT_DistFifo );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_Fifo );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_DistQueue );
  assert( p->pOrderBy==0 || pDest->eDest!=SRT_Queue );
  if( IgnorableOrderby(pDest) ){
    assert(pDest->eDest==SRT_Exists || pDest->eDest==SRT_Union || 
................................................................................

#ifndef SQLITE_OMIT_COMPOUND_SELECT
  /* If there is are a sequence of queries, do the earlier ones first.
  */
  if( p->pPrior ){
    rc = multiSelect(pParse, p, pDest);
    explainSetInteger(pParse->iSelectId, iRestoreSelectId);
#if SELECTTRACE_ENABLED
    SELECTTRACE(1,pParse,p,("end compound-select processing\n"));
    pParse->nSelectIndent--;
#endif
    return rc;
  }
#endif

  /* If the query is DISTINCT with an ORDER BY but is not an aggregate, and 
  ** if the select-list is the same as the ORDER BY list, then this query
  ** can be rewritten as a GROUP BY. In other words, this:
................................................................................
  */
  if( rc==SQLITE_OK && pDest->eDest==SRT_Output ){
    generateColumnNames(pParse, pTabList, pEList);
  }

  sqlite3DbFree(db, sAggInfo.aCol);
  sqlite3DbFree(db, sAggInfo.aFunc);
#if SELECTTRACE_ENABLED
  SELECTTRACE(1,pParse,p,("end processing\n"));
  pParse->nSelectIndent--;
#endif
  return rc;
}

#if defined(SQLITE_ENABLE_TREE_EXPLAIN)
/*
** Generate a human-readable description of a the Select object.
*/

Changes to src/shell.c.

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    }else if( rc != SQLITE_OK ){
      fprintf(stderr,"Error: querying schema information\n");
      rc = 1;
    }else{
      rc = 0;
    }
  }else










#ifdef SQLITE_DEBUG
  /* Undocumented commands for internal testing.  Subject to change
  ** without notice. */
  if( c=='s' && n>=10 && strncmp(azArg[0], "selftest-", 9)==0 ){
    if( strncmp(azArg[0]+9, "boolean", n-9)==0 ){
      int i, v;







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    }else if( rc != SQLITE_OK ){
      fprintf(stderr,"Error: querying schema information\n");
      rc = 1;
    }else{
      rc = 0;
    }
  }else


#if defined(SQLITE_DEBUG) && defined(SQLITE_ENABLE_SELECTTRACE)
  if( c=='s' && n==11 && strncmp(azArg[0], "selecttrace", n)==0 ){
    extern int sqlite3SelectTrace;
    sqlite3SelectTrace = nArg>=2 ? booleanValue(azArg[1]) : 0xff;
  }else
#endif


#ifdef SQLITE_DEBUG
  /* Undocumented commands for internal testing.  Subject to change
  ** without notice. */
  if( c=='s' && n>=10 && strncmp(azArg[0], "selftest-", 9)==0 ){
    if( strncmp(azArg[0]+9, "boolean", n-9)==0 ){
      int i, v;

Changes to src/sqliteInt.h.

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# define SQLITE_ENABLE_STAT3_OR_STAT4 1
#elif SQLITE_ENABLE_STAT3
# define SQLITE_ENABLE_STAT3_OR_STAT4 1
#elif SQLITE_ENABLE_STAT3_OR_STAT4
# undef SQLITE_ENABLE_STAT3_OR_STAT4
#endif











/*
** An instance of the following structure is used to store the busy-handler
** callback for a given sqlite handle. 
**
** The sqlite.busyHandler member of the sqlite struct contains the busy
** callback for the database handle. Each pager opened via the sqlite
** handle is passed a pointer to sqlite.busyHandler. The busy-handler
................................................................................
** sequences for the ORDER BY clause.
*/
struct Select {
  ExprList *pEList;      /* The fields of the result */
  u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
  u16 selFlags;          /* Various SF_* values */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */



  int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
  u64 nSelectRow;        /* Estimated number of result rows */
  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 */
................................................................................
  Token constraintName;/* Name of the constraint currently being parsed */
  yDbMask writeMask;   /* Start a write transaction on these databases */
  yDbMask cookieMask;  /* Bitmask of schema verified databases */
  int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
  int regRowid;        /* Register holding rowid of CREATE TABLE entry */
  int regRoot;         /* Register holding root page number for new objects */
  int nMaxArg;         /* Max args passed to user function by sub-program */




#ifndef SQLITE_OMIT_SHARED_CACHE
  int nTableLock;        /* Number of locks in aTableLock */
  TableLock *aTableLock; /* Required table locks for shared-cache mode */
#endif
  AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */

  /* Information used while coding trigger programs. */
................................................................................
void sqlite3UniqueConstraint(Parse*, int, Index*);
void sqlite3RowidConstraint(Parse*, int, Table*);
Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
IdList *sqlite3IdListDup(sqlite3*,IdList*);
Select *sqlite3SelectDup(sqlite3*,Select*,int);





void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,u8);
void sqlite3RegisterBuiltinFunctions(sqlite3*);
void sqlite3RegisterDateTimeFunctions(void);
void sqlite3RegisterGlobalFunctions(void);
int sqlite3SafetyCheckOk(sqlite3*);
int sqlite3SafetyCheckSickOrOk(sqlite3*);







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712
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714
715
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718
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720
721
722
723
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725
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# define SQLITE_ENABLE_STAT3_OR_STAT4 1
#elif SQLITE_ENABLE_STAT3
# define SQLITE_ENABLE_STAT3_OR_STAT4 1
#elif SQLITE_ENABLE_STAT3_OR_STAT4
# undef SQLITE_ENABLE_STAT3_OR_STAT4
#endif

/*
** SELECTTRACE_ENABLED will be either 1 or 0 depending on whether or not
** the Select query generator tracing logic is turned on.
*/
#if defined(SQLITE_DEBUG) || defined(SQLITE_ENABLE_SELECTTRACE)
# define SELECTTRACE_ENABLED 1
#else
# define SELECTTRACE_ENABLED 0
#endif

/*
** An instance of the following structure is used to store the busy-handler
** callback for a given sqlite handle. 
**
** The sqlite.busyHandler member of the sqlite struct contains the busy
** callback for the database handle. Each pager opened via the sqlite
** handle is passed a pointer to sqlite.busyHandler. The busy-handler
................................................................................
** sequences for the ORDER BY clause.
*/
struct Select {
  ExprList *pEList;      /* The fields of the result */
  u8 op;                 /* One of: TK_UNION TK_ALL TK_INTERSECT TK_EXCEPT */
  u16 selFlags;          /* Various SF_* values */
  int iLimit, iOffset;   /* Memory registers holding LIMIT & OFFSET counters */
#if SELECTTRACE_ENABLED
  char zSelName[12];     /* Symbolic name of this SELECT use for debugging */
#endif
  int addrOpenEphm[2];   /* OP_OpenEphem opcodes related to this select */
  u64 nSelectRow;        /* Estimated number of result rows */
  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 */
................................................................................
  Token constraintName;/* Name of the constraint currently being parsed */
  yDbMask writeMask;   /* Start a write transaction on these databases */
  yDbMask cookieMask;  /* Bitmask of schema verified databases */
  int cookieValue[SQLITE_MAX_ATTACHED+2];  /* Values of cookies to verify */
  int regRowid;        /* Register holding rowid of CREATE TABLE entry */
  int regRoot;         /* Register holding root page number for new objects */
  int nMaxArg;         /* Max args passed to user function by sub-program */
#if SELECTTRACE_ENABLED
  int nSelect;         /* Number of SELECT statements seen */
  int nSelectIndent;   /* How far to indent SELECTTRACE() output */
#endif
#ifndef SQLITE_OMIT_SHARED_CACHE
  int nTableLock;        /* Number of locks in aTableLock */
  TableLock *aTableLock; /* Required table locks for shared-cache mode */
#endif
  AutoincInfo *pAinc;  /* Information about AUTOINCREMENT counters */

  /* Information used while coding trigger programs. */
................................................................................
void sqlite3UniqueConstraint(Parse*, int, Index*);
void sqlite3RowidConstraint(Parse*, int, Table*);
Expr *sqlite3ExprDup(sqlite3*,Expr*,int);
ExprList *sqlite3ExprListDup(sqlite3*,ExprList*,int);
SrcList *sqlite3SrcListDup(sqlite3*,SrcList*,int);
IdList *sqlite3IdListDup(sqlite3*,IdList*);
Select *sqlite3SelectDup(sqlite3*,Select*,int);
#if SELECTTRACE_ENABLED
void sqlite3SelectSetName(Select*,const char*);
#else
# define sqlite3SelectSetName(A,B)
#endif
void sqlite3FuncDefInsert(FuncDefHash*, FuncDef*);
FuncDef *sqlite3FindFunction(sqlite3*,const char*,int,int,u8,u8);
void sqlite3RegisterBuiltinFunctions(sqlite3*);
void sqlite3RegisterDateTimeFunctions(void);
void sqlite3RegisterGlobalFunctions(void);
int sqlite3SafetyCheckOk(sqlite3*);
int sqlite3SafetyCheckSickOrOk(sqlite3*);

Changes to test/subquery2.test.

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106










































107
}

do_execsql_test 2.2 {
  SELECT * 
  FROM (SELECT * FROM t4 ORDER BY a LIMIT -1 OFFSET 1) 
  LIMIT (SELECT a FROM t5)
} {2 3   3 6   4 10}















































finish_test








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}

do_execsql_test 2.2 {
  SELECT * 
  FROM (SELECT * FROM t4 ORDER BY a LIMIT -1 OFFSET 1) 
  LIMIT (SELECT a FROM t5)
} {2 3   3 6   4 10}

############################################################################
# Ticket http://www.sqlite.org/src/info/d11a6e908f (2014-09-20)
# Query planner fault on three-way nested join with compound inner SELECT 
#
do_execsql_test 3.0 {
  DROP TABLE IF EXISTS t1;
  DROP TABLE IF EXISTS t2;
  CREATE TABLE t1 (id INTEGER PRIMARY KEY, data TEXT);
  INSERT INTO t1(id,data) VALUES(9,'nine-a');
  INSERT INTO t1(id,data) VALUES(10,'ten-a');
  INSERT INTO t1(id,data) VALUES(11,'eleven-a');
  CREATE TABLE t2 (id INTEGER PRIMARY KEY, data TEXT);
  INSERT INTO t2(id,data) VALUES(9,'nine-b');
  INSERT INTO t2(id,data) VALUES(10,'ten-b');
  INSERT INTO t2(id,data) VALUES(11,'eleven-b');
  
  SELECT id FROM (
    SELECT id,data FROM (
       SELECT * FROM t1 UNION ALL SELECT * FROM t2
    )
    WHERE id=10 ORDER BY data
  );
} {10 10}
do_execsql_test 3.1 {
  SELECT data FROM (
     SELECT 'dummy', data FROM (
       SELECT data FROM t1 UNION ALL SELECT data FROM t1
     ) ORDER BY data
  );
} {eleven-a eleven-a nine-a nine-a ten-a ten-a}
do_execsql_test 3.2 {
  DROP TABLE IF EXISTS t3;
  DROP TABLE IF EXISTS t4;
  CREATE TABLE t3(id INTEGER, data TEXT);
  CREATE TABLE t4(id INTEGER, data TEXT);
  INSERT INTO t3 VALUES(4, 'a'),(2,'c');
  INSERT INTO t4 VALUES(3, 'b'),(1,'d');

  SELECT data, id FROM (
    SELECT id, data FROM (
       SELECT * FROM t3 UNION ALL SELECT * FROM t4
    ) ORDER BY data
  );
} {a 4 b 3 c 2 d 1}


finish_test