From: drh <>
Date: Thu, 2 Dec 2021 01:30:16 +0000 (+0000)
Subject: Performance improvement in query planning.
X-Git-Tag: version-3.38.0~210
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9b3bfa00cd232c102e826dd9b177ad66b962f359;p=thirdparty%2Fsqlite.git

Performance improvement in query planning.

FossilOrigin-Name: ca59533bbb7f21d7b39dee7999d3f36ac516f8c75b2203039beeb2852ada42d4
---

diff --git a/manifest b/manifest
index 879da8796e..aebe38655c 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Check\sfor\sforeign\skey\sconstraint\serrors\sprior\sto\sreturning\sthe\sresults\sfrom\na\sRETURNING\sclause.\s\sSee\s[forum:/forumpost/793beaf322|forum\spost\s793beaf322].
-D 2021-12-01T19:17:14.951
+C Performance\simprovement\sin\squery\splanning.
+D 2021-12-02T01:30:16.970
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -637,7 +637,7 @@ F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
 F src/wal.c ed0398a7adf02c31e34aada42cc86c58f413a7afe5f741a5d373ad087abde028
 F src/wal.h c3aa7825bfa2fe0d85bef2db94655f99870a285778baa36307c0a16da32b226a
 F src/walker.c f890a3298418d7cba3b69b8803594fdc484ea241206a8dfa99db6dd36f8cbb3b
-F src/where.c 4b276017881185d0e1dc984df66c835cde6faf03834ef9ff34f48653f9144dec
+F src/where.c db68967fe15efdddbc067835401a0c02e2d8460daee2fdda85ca491451865170
 F src/whereInt.h 83877a75a1bce056ea44aff02f1dfa958ad1d6038c213ddadb8652003b45151d
 F src/wherecode.c 1f5b62f46d284c8886945eb7438415bc27e23e87bb60b9ee468fa6bd31268f33
 F src/whereexpr.c 17bdbf4f5b490e70a18635498f0b910a558f953a9bf80af7f19cbde6e60e6825
@@ -1933,7 +1933,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 8c986782547211098eb0e4e722eda0097421223af279381373d0055211b5e9d2
-R 21e311cc3a849b363a459e68e73e4039
+P a818ba2ed635b91e279dde44236fc7446a33db2b46c9409b67021248c01bf4e5
+R b96a809fd19be7cd4fca1d2cbe967f1c
 U drh
-Z aa1759274fb4dd09e62bccb20e559386
+Z 9b172105eb69d7dd67f53ef8928dc7e1
diff --git a/manifest.uuid b/manifest.uuid
index 22dfac2e19..b993f82b37 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-a818ba2ed635b91e279dde44236fc7446a33db2b46c9409b67021248c01bf4e5
\ No newline at end of file
+ca59533bbb7f21d7b39dee7999d3f36ac516f8c75b2203039beeb2852ada42d4
\ No newline at end of file
diff --git a/src/where.c b/src/where.c
index 54e4ea8196..fd67ac5f17 100644
--- a/src/where.c
+++ b/src/where.c
@@ -4868,12 +4868,6 @@ WhereInfo *sqlite3WhereBegin(
   if( pOrderBy && pOrderBy->nExpr>=BMS ) pOrderBy = 0;
   sWLB.pOrderBy = pOrderBy;
 
-  /* Disable the DISTINCT optimization if SQLITE_DistinctOpt is set via
-  ** sqlite3_test_ctrl(SQLITE_TESTCTRL_OPTIMIZATIONS,...) */
-  if( OptimizationDisabled(db, SQLITE_DistinctOpt) ){
-    wctrlFlags &= ~WHERE_WANT_DISTINCT;
-  }
-
   /* The number of tables in the FROM clause is limited by the number of
   ** bits in a Bitmask 
   */
@@ -4940,7 +4934,9 @@ WhereInfo *sqlite3WhereBegin(
   */
   if( nTabList==0 ){
     if( pOrderBy ) pWInfo->nOBSat = pOrderBy->nExpr;
-    if( wctrlFlags & WHERE_WANT_DISTINCT ){
+    if( (wctrlFlags & WHERE_WANT_DISTINCT)!=0
+     && OptimizationEnabled(db, SQLITE_DistinctOpt)
+    ){
       pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
     }
     ExplainQueryPlan((pParse, 0, "SCAN CONSTANT ROW"));
@@ -5001,7 +4997,12 @@ WhereInfo *sqlite3WhereBegin(
   }
 
   if( wctrlFlags & WHERE_WANT_DISTINCT ){
-    if( isDistinctRedundant(pParse, pTabList, &pWInfo->sWC, pResultSet) ){
+    if( OptimizationDisabled(db, SQLITE_DistinctOpt) ){
+      /* Disable the DISTINCT optimization if SQLITE_DistinctOpt is set via
+      ** sqlite3_test_ctrl(SQLITE_TESTCTRL_OPTIMIZATIONS,...) */
+      wctrlFlags &= ~WHERE_WANT_DISTINCT;
+      pWInfo->wctrlFlags &= ~WHERE_WANT_DISTINCT;
+    }else if( isDistinctRedundant(pParse, pTabList, &pWInfo->sWC, pResultSet) ){
       /* The DISTINCT marking is pointless.  Ignore it. */
       pWInfo->eDistinct = WHERE_DISTINCT_UNIQUE;
     }else if( pOrderBy==0 ){