Modify the query planner interface so that it always passes in the result set.

This is the first step toward adding an optimization that will omit tables
from a join that do not contribute to the result.

FossilOrigin-Name: 2c2577e69ccb47f1af674a755e71221e2ca0b322

diff --git a/manifest b/manifest
index e7e71b5de407f5973e9bc5197fd88e2546b29a54..ede3df57062df3cb4a615950616f39f4a088a071 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Add\sa\sNEVER()\smacro\sand\san\sexplanation\scomment\saround\san\sunreachable\sbranch\nin\sthe\sSTAT3\slogic.
-D 2013-06-20T17:32:28.451
+C Modify\sthe\squery\splanner\sinterface\sso\sthat\sit\salways\spasses\sin\sthe\sresult\sset.\nThis\sis\sthe\sfirst\sstep\stoward\sadding\san\soptimization\sthat\swill\somit\stables\nfrom\sa\sjoin\sthat\sdo\snot\scontribute\sto\sthe\sresult.
+D 2013-06-21T00:35:37.456
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in 5e41da95d92656a5004b03d3576e8b226858a28e
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -215,12 +215,12 @@ F src/printf.c bff529ed47657098c55c9910b9c69b1b3b1a1353
 F src/random.c cd4a67b3953b88019f8cd4ccd81394a8ddfaba50
 F src/resolve.c 89f9003e8316ee3a172795459efc2a0274e1d5a8
 F src/rowset.c 64655f1a627c9c212d9ab497899e7424a34222e0
-F src/select.c d5a1b9bc3fb451e68ce907df253c6ac17e7310f7
+F src/select.c 91b62654caf8dfe292fb8882715e575d34ad3874
 F src/shell.c ab6eea968c8745be3aa74e45fedb37d057b4cd0d
 F src/sqlite.h.in 5b390ca5d94e09e56e7fee6a51ddde4721b89f8e
 F src/sqlite3.rc fea433eb0a59f4c9393c8e6d76a6e2596b1fe0c0
 F src/sqlite3ext.h d936f797812c28b81b26ed18345baf8db28a21a5
-F src/sqliteInt.h 82a0f3e7c3410cc748c80268e0831dba5ea98cb4
+F src/sqliteInt.h cabeb0401566d80503a0bc6e2d12e7fe2577bf6d
 F src/sqliteLimit.h 164b0e6749d31e0daa1a4589a169d31c0dec7b3d
 F src/status.c bedc37ec1a6bb9399944024d63f4c769971955a9
 F src/table.c 2cd62736f845d82200acfa1287e33feb3c15d62e
@@ -289,14 +289,14 @@ F src/vtab.c b05e5f1f4902461ba9f5fc49bb7eb7c3a0741a83
 F src/wal.c 436bfceb141b9423c45119e68e444358ee0ed35d
 F src/wal.h df01efe09c5cb8c8e391ff1715cca294f89668a4
 F src/walker.c 4fa43583d0a84b48f93b1e88f11adf2065be4e73
-F src/where.c 8d6c07d9641bf107e03a2b613550d90b8c7f4a82
+F src/where.c c950b131584a40121092d735804472f567beefbc
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/aggerror.test a867e273ef9e3d7919f03ef4f0e8c0d2767944f2
 F test/aggnested.test 45c0201e28045ad38a530b5a144b73cd4aa2cfd6
 F test/alias.test 4529fbc152f190268a15f9384a5651bbbabc9d87
 F test/all.test 6ff7b43c2b4b905c74dc4a813d201d0fa64c5783
 F test/alter.test 57d96ec9b320bd07af77567034488dcb6642c748
-F test/alter2.test 7ea05c7d92ac99349a802ef7ada17294dd647060
+F test/alter2.test 40531b1f89d4fe43f9007b1bfc304e291ed000ae
 F test/alter3.test 49c9d9fba2b8fcdce2dedeca97bbf1f369cc548d
 F test/alter4.test b2debc14d8cbe4c1d12ccd6a41eef88a8c1f15d5
 F test/altermalloc.test e81ac9657ed25c6c5bb09bebfa5a047cd8e4acfc
@@ -1096,7 +1096,10 @@ F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
 F tool/wherecosttest.c f407dc4c79786982a475261866a161cd007947ae
 F tool/win/sqlite.vsix 97894c2790eda7b5bce3cc79cb2a8ec2fde9b3ac
-P d94db3fd921890ab1d6414ab629410ae50779686
-R 4877ecf4e1d53d3b49ba9f1fadfb6d66
+P 604c3c5de6fd8f8a569aa9ed981055a5b0123ba1
+R 54a7c9b08c105a408dfe2c4fd7fd4419
+T *branch * omit-join-table-opt
+T *sym-omit-join-table-opt *
+T -sym-nextgen-query-plan-exp *
 U drh
-Z c939c499a0659dd37def1fcbcc79c922
+Z d2a3072c8b463b513f8068b32a4cb830

diff --git a/manifest.uuid b/manifest.uuid
index bda94227935ef8c66dd73c58e67a77d80b8483a5..169f9d22e6a7a4dd5d4db9dac0ba1105323f2ec9 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-604c3c5de6fd8f8a569aa9ed981055a5b0123ba1
\ No newline at end of file
+2c2577e69ccb47f1af674a755e71221e2ca0b322
\ No newline at end of file

diff --git a/src/select.c b/src/select.c
index 40b7ec86f083fccdf98f657021cb135ff5f446ca..fa35f45871d70b853dcfa901ccecf65e9471ee55 100644 (file)
--- a/src/select.c
+++ b/src/select.c
@@ -4261,15 +4261,16 @@ int sqlite3Select(
 
   if( !isAgg && pGroupBy==0 ){
     /* No aggregate functions and no GROUP BY clause */
-    ExprList *pDist = (sDistinct.isTnct ? p->pEList : 0);
+    u16 wctrlFlags = (sDistinct.isTnct ? WHERE_WANT_DISTINCT : 0);
 
     /* Begin the database scan. */
-    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pOrderBy, pDist, 0,0);
+    pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, pOrderBy, p->pEList,
+                               wctrlFlags, 0);
     if( pWInfo==0 ) goto select_end;
     if( sqlite3WhereOutputRowCount(pWInfo) < p->nSelectRow ){
       p->nSelectRow = sqlite3WhereOutputRowCount(pWInfo);
     }
-    if( sqlite3WhereIsDistinct(pWInfo) ){
+    if( sDistinct.isTnct && sqlite3WhereIsDistinct(pWInfo) ){
       sDistinct.eTnctType = sqlite3WhereIsDistinct(pWInfo);
     }
     if( pOrderBy && sqlite3WhereIsOrdered(pWInfo) ) pOrderBy = 0;

diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index b2cab7a7ad1cde7258be4587cc5fe25190e172c4..731612d3457ba21b8777112027750c3578d02953 100644 (file)
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -1974,6 +1974,7 @@ struct SrcList {
 #define WHERE_AND_ONLY         0x0080 /* Don't use indices for OR terms */
 #define WHERE_GROUPBY          0x0100 /* pOrderBy is really a GROUP BY */
 #define WHERE_DISTINCTBY       0x0200 /* pOrderby is really a DISTINCT clause */
+#define WHERE_WANT_DISTINCT    0x0400 /* All output needs to be distinct */
 
 /* Allowed return values from sqlite3WhereIsDistinct()
 */

diff --git a/src/where.c b/src/where.c
index cdc0e168390582b73e7a6e3cf1c88e3bd0dd103b..ab4170fe6fe7c94ad9324cf3e057d20cc668056e 100644 (file)
--- a/src/where.c
+++ b/src/where.c
@@ -383,7 +383,7 @@ struct WhereInfo {
   Parse *pParse;            /* Parsing and code generating context */
   SrcList *pTabList;        /* List of tables in the join */
   ExprList *pOrderBy;       /* The ORDER BY clause or NULL */
-  ExprList *pDistinct;      /* DISTINCT ON values, or NULL */
+  ExprList *pResultSet;     /* Result set. DISTINCT operates on these */
   WhereLoop *pLoops;        /* List of all WhereLoop objects */
   Bitmask revMask;          /* Mask of ORDER BY terms that need reversing */
   WhereCost nRowOut;        /* Estimated number of output rows */
@@ -3928,9 +3928,9 @@ static void whereLoopPrint(WhereLoop *p, SrcList *pTabList){
   int nb = 1+(pTabList->nSrc+7)/8;
   struct SrcList_item *pItem = pTabList->a + p->iTab;
   Table *pTab = pItem->pTab;
-  sqlite3DebugPrintf("%c %2d.%0*llx.%0*llx", p->cId,
+  sqlite3DebugPrintf("%c%2d.%0*llx.%0*llx", p->cId,
                      p->iTab, nb, p->maskSelf, nb, p->prereq);
-  sqlite3DebugPrintf(" %8s",
+  sqlite3DebugPrintf(" %12s",
                      pItem->zAlias ? pItem->zAlias : pTab->zName);
   if( (p->wsFlags & WHERE_VIRTUALTABLE)==0 ){
     if( p->u.btree.pIndex ){
@@ -3941,9 +3941,9 @@ static void whereLoopPrint(WhereLoop *p, SrcList *pTabList){
         while( zName[i]!='_' ) i--;
         zName += i;
       }
-      sqlite3DebugPrintf(".%-12s %2d", zName, p->u.btree.nEq);
+      sqlite3DebugPrintf(".%-16s %2d", zName, p->u.btree.nEq);
     }else{
-      sqlite3DebugPrintf("%16s","");
+      sqlite3DebugPrintf("%20s","");
     }
   }else{
     char *z;
@@ -3953,10 +3953,10 @@ static void whereLoopPrint(WhereLoop *p, SrcList *pTabList){
     }else{
       z = sqlite3_mprintf("(%d,%x)", p->u.vtab.idxNum, p->u.vtab.omitMask);
     }
-    sqlite3DebugPrintf(" %-15s", z);
+    sqlite3DebugPrintf(" %-19s", z);
     sqlite3_free(z);
   }
-  sqlite3DebugPrintf(" fg %05x N %d", p->wsFlags, p->nLTerm);
+  sqlite3DebugPrintf(" f %04x N %d", p->wsFlags, p->nLTerm);
   sqlite3DebugPrintf(" cost %d,%d,%d\n", p->rSetup, p->rRun, p->nOut);
 }
 #endif
@@ -5370,12 +5370,12 @@ static int wherePathSolver(WhereInfo *pWInfo, WhereCost nRowEst){
     pLevel->iFrom = pWLoop->iTab;
     pLevel->iTabCur = pWInfo->pTabList->a[pLevel->iFrom].iCursor;
   }
-  if( (pWInfo->wctrlFlags & WHERE_DISTINCTBY)==0 
-   && pWInfo->pDistinct
+  if( (pWInfo->wctrlFlags & (WHERE_DISTINCTBY|WHERE_WANT_DISTINCT))
+                ==WHERE_WANT_DISTINCT
    && nRowEst
   ){
     Bitmask notUsed;
-    int rc = wherePathSatisfiesOrderBy(pWInfo, pWInfo->pDistinct, pFrom,
+    int rc = wherePathSatisfiesOrderBy(pWInfo, pWInfo->pResultSet, pFrom,
                  WHERE_DISTINCTBY, nLoop-1, pFrom->aLoop[nLoop-1], &notUsed);
     if( rc==1 ) pWInfo->eDistinct = WHERE_DISTINCT_ORDERED;
   }
@@ -5464,7 +5464,9 @@ static int whereShortCut(WhereLoopBuilder *pBuilder){
     pWInfo->a[0].iTabCur = iCur;
     pWInfo->nRowOut = 1;
     if( pWInfo->pOrderBy ) pWInfo->bOBSat =  1;
-    if( pWInfo->pDistinct ) pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
+    if( pWInfo->wctrlFlags & WHERE_WANT_DISTINCT ){
+      pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
+    }
 #ifdef SQLITE_DEBUG
     pLoop->cId = '0';
 #endif
@@ -5554,10 +5556,10 @@ static int whereShortCut(WhereLoopBuilder *pBuilder){
 */
 WhereInfo *sqlite3WhereBegin(
   Parse *pParse,        /* The parser context */
-  SrcList *pTabList,    /* A list of all tables to be scanned */
+  SrcList *pTabList,    /* FROM clause: A list of all tables to be scanned */
   Expr *pWhere,         /* The WHERE clause */
   ExprList *pOrderBy,   /* An ORDER BY clause, or NULL */
-  ExprList *pDistinct,  /* The select-list for DISTINCT queries - or NULL */
+  ExprList *pResultSet, /* Result set of the query */
   u16 wctrlFlags,       /* One of the WHERE_* flags defined in sqliteInt.h */
   int iIdxCur           /* If WHERE_ONETABLE_ONLY is set, index cursor number */
 ){
@@ -5613,7 +5615,7 @@ WhereInfo *sqlite3WhereBegin(
   pWInfo->pParse = pParse;
   pWInfo->pTabList = pTabList;
   pWInfo->pOrderBy = pOrderBy;
-  pWInfo->pDistinct = pDistinct;
+  pWInfo->pResultSet = pResultSet;
   pWInfo->iBreak = sqlite3VdbeMakeLabel(v);
   pWInfo->wctrlFlags = wctrlFlags;
   pWInfo->savedNQueryLoop = pParse->nQueryLoop;
@@ -5628,7 +5630,9 @@ WhereInfo *sqlite3WhereBegin(
 
   /* Disable the DISTINCT optimization if SQLITE_DistinctOpt is set via
   ** sqlite3_test_ctrl(SQLITE_TESTCTRL_OPTIMIZATIONS,...) */
-  if( OptimizationDisabled(db, SQLITE_DistinctOpt) ) pDistinct = 0;
+  if( OptimizationDisabled(db, SQLITE_DistinctOpt) ){
+    wctrlFlags &= ~WHERE_WANT_DISTINCT;
+  }
 
   /* Split the WHERE clause into separate subexpressions where each
   ** subexpression is separated by an AND operator.
@@ -5650,7 +5654,9 @@ WhereInfo *sqlite3WhereBegin(
   */
   if( nTabList==0 ){
     if( pOrderBy ) pWInfo->bOBSat = 1;
-    if( pDistinct ) pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
+    if( wctrlFlags & WHERE_WANT_DISTINCT ){
+      pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
+    }
   }
 
   /* Assign a bit from the bitmask to every term in the FROM clause.
@@ -5697,7 +5703,7 @@ WhereInfo *sqlite3WhereBegin(
   ** expressions, then we won't be able to satisfy it using indices, so
   ** go ahead and disable it now.
   */
-  if( pOrderBy && pDistinct ){
+  if( pOrderBy && (wctrlFlags & WHERE_WANT_DISTINCT)!=0 ){
     for(ii=0; ii<pOrderBy->nExpr; ii++){
       Expr *pExpr = sqlite3ExprSkipCollate(pOrderBy->a[ii].pExpr);
       if( pExpr->op!=TK_COLUMN ){
@@ -5709,17 +5715,15 @@ WhereInfo *sqlite3WhereBegin(
     }
   }
 
-  /* Check if the DISTINCT qualifier, if there is one, is redundant. 
-  ** If it is, then set pDistinct to NULL and WhereInfo.eDistinct to
-  ** WHERE_DISTINCT_UNIQUE to tell the caller to ignore the DISTINCT.
-  */
-  if( pDistinct ){
-    if( isDistinctRedundant(pParse,pTabList,&pWInfo->sWC,pDistinct) ){
-      pDistinct = 0;
+  if( wctrlFlags & WHERE_WANT_DISTINCT ){
+    if( isDistinctRedundant(pParse, pTabList, &pWInfo->sWC, pResultSet) ){
+      /* The DISTINCT marking is pointless.  Ignore it. */
+      wctrlFlags &= ~WHERE_WANT_DISTINCT;
       pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
     }else if( pOrderBy==0 ){
+      /* Try to ORDER BY the result set to make distinct processing easier */
       pWInfo->wctrlFlags |= WHERE_DISTINCTBY;
-      pWInfo->pOrderBy = pDistinct;
+      pWInfo->pOrderBy = pResultSet;
     }
   }
 

diff --git a/test/alter2.test b/test/alter2.test
index 14be637f970ffd3a6a6875420a2196faf3e05a71..db8a83bf9f935df8119c2badad9abbef55e5068d 100644 (file)
--- a/test/alter2.test
+++ b/test/alter2.test
@@ -120,6 +120,7 @@ do_test alter2-1.5 {
   }
 } {}
 do_test alter2-1.6 {
+breakpoint
   execsql {
     SELECT c FROM abc ORDER BY c;
   }