From: drh <>
Date: Thu, 21 Jan 2021 17:54:41 +0000 (+0000)
Subject: Always enable the IS NOT NULL optimization, even if STAT4 is not enabled.
X-Git-Tag: version-3.35.0~126^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=6cca0aa9df3d4e18fd7eed0b9867120e6cc1e482;p=thirdparty%2Fsqlite.git

Always enable the IS NOT NULL optimization, even if STAT4 is not enabled.

FossilOrigin-Name: fc98218cf69e63bdb9e5f154521a341508502cd8cfe04cb870cabee2d99e0cb3
---

diff --git a/manifest b/manifest
index c2ea1b0e81..008fa8c252 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\sa\sproblem\scaused\sby\susing\san\sSQL\svariable\sin\san\sOVER\sclause\swithin\sa\strigger\sprogram.
-D 2021-01-21T16:02:14.840
+C Always\senable\sthe\sIS\sNOT\sNULL\soptimization,\seven\sif\sSTAT4\sis\snot\senabled.
+D 2021-01-21T17:54:41.795
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -629,9 +629,9 @@ F src/wal.c 69e770e96fd56cc21608992bf2c6f1f3dc5cf2572d0495c6a643b06c3a679f14
 F src/wal.h c3aa7825bfa2fe0d85bef2db94655f99870a285778baa36307c0a16da32b226a
 F src/walker.c d9c4e454ebb9499e908aa62d55b8994c375cf5355ac78f60d45af17f7890701c
 F src/where.c 0e6abb22a2323fec80b450825593c26a2ad8f4815d1ee3af9969d8f6144bf681
-F src/whereInt.h 9a3f577619f07700d16d89eeb2f3d94d6b7ed7f109c2dacf0ce8844921549506
+F src/whereInt.h ae03b5e3a4cca9bd9cb1b7d3c63faf8f1f177200fc8cecc87d3d0cab6ca338e6
 F src/wherecode.c a3a1aff30fe99a818d8e7c607980f033f40c68d890e03ed25838b9dbb7908bee
-F src/whereexpr.c a022b4f447c0fb0674e172a9a303537ea5055df60d579f99cec7ead18e8c453f
+F src/whereexpr.c 1f11bdd204ad021f5935df6e7726b4f1dbdd3157a4f31d0dafc9c457e5e545a8
 F src/window.c edd6f5e25a1e8f2b6f5305b7f5f7da7bb35f07f0d432b255b1d4c2fcab4205aa
 F test/8_3_names.test ebbb5cd36741350040fd28b432ceadf495be25b2
 F test/affinity2.test ce1aafc86e110685b324e9a763eab4f2a73f737842ec3b687bd965867de90627
@@ -1898,8 +1898,10 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P d1873054d8e1006a370ea7891dbb9a62e7d36ce98cb92b58dcb0daf271265de3 4f676466e60ee2a420b7b2deace76f3a733ce1af278347428285715d9c67f022
-R 56f323b51c91a7109bc328027a56f7a2
-T +closed 4f676466e60ee2a420b7b2deace76f3a733ce1af278347428285715d9c67f022
-U dan
-Z af485d37bfb17e22d383f2711ee5f268
+P 02264ab6a02d6cc95cf865920bcbaf4307d034640e6e4f3371b009ae9818540e
+R 8df6cd517dfa239c965fc40092a79782
+T *branch * isnotnull-opt
+T *sym-isnotnull-opt *
+T -sym-trunk *
+U drh
+Z d06e074a8f142c72ee8a673bfd500f4d
diff --git a/manifest.uuid b/manifest.uuid
index 57afc8f5ef..1e251fa4a5 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-02264ab6a02d6cc95cf865920bcbaf4307d034640e6e4f3371b009ae9818540e
\ No newline at end of file
+fc98218cf69e63bdb9e5f154521a341508502cd8cfe04cb870cabee2d99e0cb3
\ No newline at end of file
diff --git a/src/whereInt.h b/src/whereInt.h
index f8509996fa..89a463dc38 100644
--- a/src/whereInt.h
+++ b/src/whereInt.h
@@ -270,11 +270,7 @@ struct WhereTerm {
 #define TERM_ORINFO     0x0010 /* Need to free the WhereTerm.u.pOrInfo object */
 #define TERM_ANDINFO    0x0020 /* Need to free the WhereTerm.u.pAndInfo obj */
 #define TERM_OR_OK      0x0040 /* Used during OR-clause processing */
-#ifdef SQLITE_ENABLE_STAT4
-#  define TERM_VNULL    0x0080 /* Manufactured x>NULL or x<=NULL term */
-#else
-#  define TERM_VNULL    0x0000 /* Disabled if not using stat4 */
-#endif
+#define TERM_VNULL      0x0080 /* Manufactured x>NULL or x<=NULL term */
 #define TERM_LIKEOPT    0x0100 /* Virtual terms from the LIKE optimization */
 #define TERM_LIKECOND   0x0200 /* Conditionally this LIKE operator term */
 #define TERM_LIKE       0x0400 /* The original LIKE operator */
diff --git a/src/whereexpr.c b/src/whereexpr.c
index 5cfdad67c1..0dc56ea8a3 100644
--- a/src/whereexpr.c
+++ b/src/whereexpr.c
@@ -1466,6 +1466,41 @@ static void exprAnalyze(
     }
   }
 
+  /* The form "x IS NOT NULL" can sometimes be evaluated more efficiently
+  ** as "x>NULL" if x is not an INTEGER PRIMARY KEY.  So construct a
+  ** virtual term of that form.
+  **
+  ** The virtual term must be tagged with TERM_VNULL.
+  */
+  else if( pExpr->op==TK_NOTNULL ){
+    if( pExpr->pLeft->op==TK_COLUMN
+     && pExpr->pLeft->iColumn>=0
+     && !ExprHasProperty(pExpr, EP_FromJoin)
+    ){
+      Expr *pNewExpr;
+      Expr *pLeft = pExpr->pLeft;
+      int idxNew;
+      WhereTerm *pNewTerm;
+  
+      pNewExpr = sqlite3PExpr(pParse, TK_GT,
+                              sqlite3ExprDup(db, pLeft, 0),
+                              sqlite3ExprAlloc(db, TK_NULL, 0, 0));
+  
+      idxNew = whereClauseInsert(pWC, pNewExpr,
+                                TERM_VIRTUAL|TERM_DYNAMIC|TERM_VNULL);
+      if( idxNew ){
+        pNewTerm = &pWC->a[idxNew];
+        pNewTerm->prereqRight = 0;
+        pNewTerm->leftCursor = pLeft->iTable;
+        pNewTerm->u.x.leftColumn = pLeft->iColumn;
+        pNewTerm->eOperator = WO_GT;
+        markTermAsChild(pWC, idxNew, idxTerm);
+        pTerm = &pWC->a[idxTerm];
+        pTerm->wtFlags |= TERM_COPIED;
+        pNewTerm->prereqAll = pTerm->prereqAll;
+      }
+    }
+  }
 
 #ifndef SQLITE_OMIT_LIKE_OPTIMIZATION
   /* Add constraints to reduce the search space on a LIKE or GLOB
@@ -1637,7 +1672,9 @@ static void exprAnalyze(
   ** This only works if the RHS is a simple SELECT (not a compound) that does
   ** not use window functions.
   */
-  if( pWC->op==TK_AND && pExpr->op==TK_IN && pTerm->u.x.iField==0
+  if( pWC->op==TK_AND
+   && pExpr->op==TK_IN
+   && pTerm->u.x.iField==0
    && pExpr->pLeft->op==TK_VECTOR
    && pExpr->x.pSelect->pPrior==0
 #ifndef SQLITE_OMIT_WINDOWFUNC
@@ -1654,45 +1691,6 @@ static void exprAnalyze(
     }
   }
 
-#ifdef SQLITE_ENABLE_STAT4
-  /* When sqlite_stat4 histogram data is available an operator of the
-  ** form "x IS NOT NULL" can sometimes be evaluated more efficiently
-  ** as "x>NULL" if x is not an INTEGER PRIMARY KEY.  So construct a
-  ** virtual term of that form.
-  **
-  ** Note that the virtual term must be tagged with TERM_VNULL.
-  */
-  if( pExpr->op==TK_NOTNULL
-   && pExpr->pLeft->op==TK_COLUMN
-   && pExpr->pLeft->iColumn>=0
-   && !ExprHasProperty(pExpr, EP_FromJoin)
-   && OptimizationEnabled(db, SQLITE_Stat4)
-  ){
-    Expr *pNewExpr;
-    Expr *pLeft = pExpr->pLeft;
-    int idxNew;
-    WhereTerm *pNewTerm;
-
-    pNewExpr = sqlite3PExpr(pParse, TK_GT,
-                            sqlite3ExprDup(db, pLeft, 0),
-                            sqlite3ExprAlloc(db, TK_NULL, 0, 0));
-
-    idxNew = whereClauseInsert(pWC, pNewExpr,
-                              TERM_VIRTUAL|TERM_DYNAMIC|TERM_VNULL);
-    if( idxNew ){
-      pNewTerm = &pWC->a[idxNew];
-      pNewTerm->prereqRight = 0;
-      pNewTerm->leftCursor = pLeft->iTable;
-      pNewTerm->u.x.leftColumn = pLeft->iColumn;
-      pNewTerm->eOperator = WO_GT;
-      markTermAsChild(pWC, idxNew, idxTerm);
-      pTerm = &pWC->a[idxTerm];
-      pTerm->wtFlags |= TERM_COPIED;
-      pNewTerm->prereqAll = pTerm->prereqAll;
-    }
-  }
-#endif /* SQLITE_ENABLE_STAT4 */
-
   /* Prevent ON clause terms of a LEFT JOIN from being used to drive
   ** an index for tables to the left of the join.
   */