The same restrictions on the use of WHERE clause terms to drive indexes

in the presence of RIGHT JOINs also apply to the use of WHERE clause terms
to manufacture automatic indexes.  This fixes a problem identified by
[forum:/forumpost/51e6959f61|forum post 51e6959f61].

FossilOrigin-Name: 342c501f532523347e6c339351e02043dd6ee9e11a291224b65ea72bd6c2ba40

manifest

@@ -1,5 +1,5 @@
-C fiddle:\sminor\sstyle\stweaks,\sincluding\susing\sswapped\scolors\sfor\sthe\sinput/output\sfields\sto\shelp\s(hopefully)\sreduce\sthe\s"which\sfield\sis\swhich?"\sdissonance.
-D 2022-06-10T15:43:03.260
+C The\ssame\srestrictions\son\sthe\suse\sof\sWHERE\sclause\sterms\sto\sdrive\sindexes\nin\sthe\spresence\sof\sRIGHT\sJOINs\salso\sapply\sto\sthe\suse\sof\sWHERE\sclause\sterms\nto\smanufacture\sautomatic\sindexes.\s\sThis\sfixes\sa\sproblem\sidentified\sby\n[forum:/forumpost/51e6959f61|forum\spost\s51e6959f61].
+D 2022-06-10T16:41:54.319
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -657,7 +657,7 @@ F src/vxworks.h d2988f4e5a61a4dfe82c6524dd3d6e4f2ce3cdb9
 F src/wal.c b9df133a705093da8977da5eb202eaadb844839f1c7297c08d33471f5491843d
 F src/wal.h c3aa7825bfa2fe0d85bef2db94655f99870a285778baa36307c0a16da32b226a
 F src/walker.c f890a3298418d7cba3b69b8803594fdc484ea241206a8dfa99db6dd36f8cbb3b
-F src/where.c 7a5c084800eab6ed9006bccd5d3116a7a6a998c56c525b22f62f131b3b133189
+F src/where.c 267caa227dd38ede46959468118ef4067316dae589d889c200911ff77df53ef1
 F src/whereInt.h b48ca529ffe293c18cbfa8326af18a09e39910de66fb3e96ef788c7cbf8ef3a7
 F src/wherecode.c 0b09abfcb88c61c6a6984a3e065786631ff35495e9bdf865e6b74ab0a1299c5b
 F src/whereexpr.c 20255cf03e0b765b742301197d165511ff99e95da0d7ee9c8a2ebc1e888dd049
@@ -1167,7 +1167,7 @@ F test/join4.test 1a352e4e267114444c29266ce79e941af5885916
 F test/join5.test d22b6cba8fb59ab3f1c82701434c360705eb12d4ce200c449f37b018fc47681a
 F test/join6.test f809c025fa253f9e150c0e9afd4cef8813257bceeb6f46e04041228c9403cc2c
 F test/join7.test 2268dcbb54b724391dda3748ea95c60d960607ffeed67885675998e7117697f6
-F test/join8.test ca277bf3c03a2fdcc4bccfadb178828350c9bae1354a3410b2c3d46f61e62a10
+F test/join8.test 135277faf0cab04efe42bfea9aadde034bd36dc2ce3a3de49e97c8c7f745f103
 F test/join9.test 9056ddd3b0c0f4f9d658f4521038d9a37dc23ead8ca9a505d0b0db2b6a471e05
 F test/joinA.test 7eab225dc1c1ab258a5e62513a4ed7cabbd3db971d59d5d92f4fb6fa14c12f6a
 F test/joinB.test 1b2ba3fc8568b49411787fccbf540570c148e9b6a53a30f80691cb6268098ded
@@ -1976,8 +1976,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P cab9b4cccd13bf0ab2bc38dc9a9c04ddd34e29c65ab6aef07b6bb3c31a43bece
-R 29ea6fa57e08e2764252fc42ded3b3ec
-U stephan
-Z 4b738143df3568b63c5639bf0ffc2bc2
+P e25dad868f9ef2c7847319c9f6f106999ba8b0a3e09ed9edfbd25e8fc6f3c10e
+R 71f93056490b18abe7ae590f710ffb97
+U drh
+Z c3464bb306b9115d0a59088775264fcc
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-e25dad868f9ef2c7847319c9f6f106999ba8b0a3e09ed9edfbd25e8fc6f3c10e
+342c501f532523347e6c339351e02043dd6ee9e11a291224b65ea72bd6c2ba40

src/where.c

@@ -757,14 +757,17 @@ static int termCanDriveIndex(
   char aff;
   if( pTerm->leftCursor!=pSrc->iCursor ) return 0;
   if( (pTerm->eOperator & (WO_EQ|WO_IS))==0 ) return 0;
-  if( (pSrc->fg.jointype & (JT_LEFT|JT_LTORJ))!=0
-   && !ExprHasProperty(pTerm->pExpr, EP_OuterON)
-   && (pTerm->eOperator & WO_IS)
-  ){
-    /* Cannot use an IS term from the WHERE clause as an index driver for
-    ** the RHS of a LEFT JOIN or for the LHS of a RIGHT JOIN. Such a term
-    ** can only be used if it is from the ON clause.  */
-    return 0;
+  assert( (pSrc->fg.jointype & JT_RIGHT)==0 );
+  if( (pSrc->fg.jointype & (JT_LEFT|JT_LTORJ|JT_RIGHT))!=0 ){
+    testcase( (pSrc->fg.jointype & (JT_LEFT|JT_LTORJ|JT_RIGHT))==JT_LEFT );
+    testcase( (pSrc->fg.jointype & (JT_LEFT|JT_LTORJ|JT_RIGHT))==JT_LTORJ );
+    testcase( ExprHasProperty(pTerm->pExpr, EP_OuterON) )
+    testcase( ExprHasProperty(pTerm->pExpr, EP_InnerON) );
+    if( !ExprHasProperty(pTerm->pExpr, EP_OuterON|EP_InnerON)
+     || pTerm->pExpr->w.iJoin != pSrc->iCursor
+    ){
+      return 0;  /* See tag-20191211-001 */
+    }
   }
   if( (pTerm->prereqRight & notReady)!=0 ) return 0;
   assert( (pTerm->eOperator & (WO_OR|WO_AND))==0 );
@@ -2848,6 +2851,9 @@ static int whereLoopAddBtreeIndex(
     ** for an example of a WHERE clause constraints that may not be used on
     ** the right table of a RIGHT JOIN because the constraint implies a
     ** not-NULL condition on the left table of the RIGHT JOIN.
+    **
+    ** 2022-06-10: The same condition applies to termCanDriveIndex() above.
+    ** https://sqlite.org/forum/forumpost/51e6959f61
     */
     if( (pSrc->fg.jointype & (JT_LEFT|JT_LTORJ|JT_RIGHT))!=0 ){
       testcase( (pSrc->fg.jointype & (JT_LEFT|JT_LTORJ|JT_RIGHT))==JT_LEFT );

test/join8.test

@@ -674,6 +674,26 @@ do_execsql_test join8-21010 {
 do_execsql_test join8-22020 {
   SELECT * FROM t1 JOIN t3 ON (b=TRUE) RIGHT JOIN t2 ON TRUE WHERE (b IS TRUE);
 } {}
+
+# 2022-06-10
+# https://sqlite.org/forum/forumpost/51e6959f61
+#
+# Restrictions on the usage of WHERE clause constraints by joins that are
+# involved with a RIGHT JOIN must also be applied to automatic indexes.
+#
+reset_db
+do_execsql_test join8-22000 {
+  CREATE TABLE t1(a INT);
+  CREATE TABLE t2(b INT);
+  CREATE TABLE t3(c TEXT);  INSERT INTO t3 VALUES('x');
+  CREATE TABLE t4(d TEXT);  INSERT INTO t4 VALUES('y');
+  SELECT 99
+    FROM t1
+         LEFT JOIN t2 ON true
+         RIGHT JOIN t3 ON true
+         RIGHT JOIN t4 ON true
+   WHERE a=b;
+} {}
   
 
 finish_test