From 0186ee1cd742a78f8b98fd1ec7e197aaf8f1c2f8 Mon Sep 17 00:00:00 2001
From: drh <>
Date: Sat, 25 Jan 2025 14:30:36 +0000
Subject: [PATCH] Improvments to debug output on the star-query heuristic.

FossilOrigin-Name: b3ebeb0682a2c837987acf4ed92f06cf91aea235830c5a0f9dd1ce64afe16e84
---
 manifest        | 14 +++++++-------
 manifest.uuid   |  2 +-
 src/sqliteInt.h |  4 +++-
 src/where.c     | 22 +++++++++++++++++-----
 4 files changed, 28 insertions(+), 14 deletions(-)

diff --git a/manifest b/manifest
index ec0df49442..b407f7242e 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Avoid\scalling\scomputeMxChoice()\safter\san\sOOM\sas\ssome\sassert()s\scan\sfail\nin\sthat\sroutine\sif\sa\sprior\sOOM\soccurred\swhile\sbuilding\sthe\sWhereLoop\sarray.
-D 2025-01-25T00:07:14.255
+C Improvments\sto\sdebug\soutput\son\sthe\sstar-query\sheuristic.
+D 2025-01-25T14:30:36.057
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md e108e1e69ae8e8a59e93c455654b8ac9356a11720d3345df2a4743e9590fb20d
@@ -784,7 +784,7 @@ F src/shell.c.in 9ade75afa953c5c2ded38d076533eaa6c9b2ab1977ef6cce0bc773adac178c5
 F src/sqlite.h.in 135c4479d03d5dcff7f580c1997f351d94954cf37346db560948c7add6159d9a
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 3f046c04ea3595d6bfda99b781926b17e672fd6d27da2ba6d8d8fc39981dcb54
-F src/sqliteInt.h 953f2476f712b115ecb43f7a21183d07c88af8d3b4c32f18317724ce1ce04d56
+F src/sqliteInt.h e28d3ad85c671effec0892f156e1e0f949733fb0995335406b5ec3803faba3a4
 F src/sqliteLimit.h 1bbdbf72bd0411d003267ffebc59a262f061df5653027a75627d03f48ca30523
 F src/status.c cb11f8589a6912af2da3bb1ec509a94dd8ef27df4d4c1a97e0bcf2309ece972b
 F src/table.c 0f141b58a16de7e2fbe81c308379e7279f4c6b50eb08efeec5892794a0ba30d1
@@ -863,7 +863,7 @@ F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
 F src/wal.c 4e6181d8780ab0af2e1388d0754cbe6f2f04593d2b1ab6c41699a89942fd8997
 F src/wal.h ba252daaa94f889f4b2c17c027e823d9be47ce39da1d3799886bbd51f0490452
 F src/walker.c d5006d6b005e4ea7302ad390957a8d41ed83faa177e412f89bc5600a7462a014
-F src/where.c 75427197cc4a6251f7e643c27512a846593a8fc349381ca210b8e1c5b87c5fdb
+F src/where.c 8fb5ce22e5fbc82f8e53a059e76ff492113f3de8ff26c3639d52c75e94088596
 F src/whereInt.h 3b2ef4617758174d00c6940850e4988c1b195d39bcc20f2965319a1f7bffc714
 F src/wherecode.c 0c3d3199a2b769a5e2bb70feb5003dc85b3d86842ecaf903a47f2b4205ca5dab
 F src/whereexpr.c 0f93a29cabd3a338d09a1f5c6770620a1ac51ec1157f3229502a7e7767c60b6f
@@ -2208,8 +2208,8 @@ F tool/version-info.c 3b36468a90faf1bbd59c65fd0eb66522d9f941eedd364fabccd7227350
 F tool/warnings-clang.sh bbf6a1e685e534c92ec2bfba5b1745f34fb6f0bc2a362850723a9ee87c1b31a7
 F tool/warnings.sh 49a486c5069de041aedcbde4de178293e0463ae9918ecad7539eedf0ec77a139
 F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 431a1a29f93dc642779dc21c3a0edad5fcda1d175e9d1e3b216fa02c234fe774
-R 5b1c7e21f9360cd4e11f23b85175a095
+P 8b9e621dbf599d7e75e07d75d4c400247d693ea76e00eba0919f4e33e3e10bdd
+R e6dd9f24405ca06acecad76b774b4e57
 U drh
-Z 397108c3fd80a1eae2be914e45c3c459
+Z 5c57dd71c02ea0fa33cecfe1d8ec4eed
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index 848e01e8a7..a25e3e3f14 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-8b9e621dbf599d7e75e07d75d4c400247d693ea76e00eba0919f4e33e3e10bdd
+b3ebeb0682a2c837987acf4ed92f06cf91aea235830c5a0f9dd1ce64afe16e84
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 3045d7c4a5..d29b2e3930 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -1151,7 +1151,7 @@ extern u32 sqlite3WhereTrace;
 ** 0xFFFF----   Low-level debug messages
 **
 ** 0x00000001   Code generation
-** 0x00000002   Solver
+** 0x00000002   Solver (Use 0x40000 for less detail)
 ** 0x00000004   Solver costs
 ** 0x00000008   WhereLoop inserts
 **
@@ -1170,6 +1170,8 @@ extern u32 sqlite3WhereTrace;
 **
 ** 0x00010000   Show more detail when printing WHERE terms
 ** 0x00020000   Show WHERE terms returned from whereScanNext()
+** 0x00040000   Solver overview messages
+** 0x00080000   Star-query heuristic
 */
 
 
diff --git a/src/where.c b/src/where.c
index 24674f91df..d25a1723d3 100644
--- a/src/where.c
+++ b/src/where.c
@@ -5544,8 +5544,8 @@ static int computeMxChoice(WhereInfo *pWInfo){
       }
       if( nDep<=3 ) continue;
       rDelta = 15*(nDep-3);
-#ifdef WHERETRACE_ENABLED /* 0x4 */
-      if( sqlite3WhereTrace&0x4 ){
+#ifdef WHERETRACE_ENABLED /* 0x80000 */
+      if( sqlite3WhereTrace & 0x80000 ){
         Bitmask x;
         int ii;
         sqlite3DebugPrintf(
@@ -5564,10 +5564,12 @@ static int computeMxChoice(WhereInfo *pWInfo){
         sqlite3DebugPrintf("\n");
       }
 #endif
-      for(pWLoop=pWInfo->pLoops; pWLoop; pWLoop=pWLoop->pNextLoop){
-        pWLoop->rStarDelta = 0;
+      if( pWInfo->nOutStarDelta==0 ){
+        for(pWLoop=pWInfo->pLoops; pWLoop; pWLoop=pWLoop->pNextLoop){
+          pWLoop->rStarDelta = 0;
+        }
       }
-      pWInfo->nOutStarDelta = rDelta;
+      pWInfo->nOutStarDelta += rDelta;
       for(pWLoop=pWInfo->pLoops; pWLoop; pWLoop=pWLoop->pNextLoop){
         if( pWLoop->maskSelf==m ){
           pWLoop->rRun -= rDelta;
@@ -5576,6 +5578,16 @@ static int computeMxChoice(WhereInfo *pWInfo){
         }
       }
     }
+#ifdef WHERETRACE_ENABLED /* 0x80000 */
+    if( (sqlite3WhereTrace & 0x80000)!=0 && pWInfo->nOutStarDelta ){
+      sqlite3DebugPrintf("WhereLoops changed by star-query heuristic:\n");
+      for(pWLoop=pWInfo->pLoops; pWLoop; pWLoop=pWLoop->pNextLoop){
+        if( pWLoop->rStarDelta ){
+          sqlite3WhereLoopPrint(pWLoop, &pWInfo->sWC);
+        }
+      }
+    }
+#endif
   }
   return pWInfo->nOutStarDelta>0 ? 18 : 12;
 }
-- 
2.47.2