Add the stub function: optimizeAggregateUsingIndexedExpr(). The hope is that

we can fill this in with a routine that does useful optimizations.

FossilOrigin-Name: d85bb724fdd6fbad2b88ed7f60e4174e3f65182356f404d04620c5cf6b17f77e

manifest

@@ -1,5 +1,5 @@
-C Merge\strunk\sfixes\sand\senhancements\sinto\sthe\sagg-with-indexed-expr\sbranch.
-D 2022-11-22T19:51:16.237
+C Add\sthe\sstub\sfunction:\soptimizeAggregateUsingIndexedExpr().\s\sThe\shope\sis\sthat\nwe\scan\sfill\sthis\sin\swith\sa\sroutine\sthat\sdoes\suseful\soptimizations.
+D 2022-11-22T20:37:41.721
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -641,7 +641,7 @@ F src/printf.c e99ee9741e79ae3873458146f59644276657340385ade4e76a5f5d1c25793764
 F src/random.c 606b00941a1d7dd09c381d3279a058d771f406c5213c9932bbd93d5587be4b9c
 F src/resolve.c efea4e5fbecfd6d0a9071b0be0d952620991673391b6ffaaf4c277b0bb674633
 F src/rowset.c ba9515a922af32abe1f7d39406b9d35730ed65efab9443dc5702693b60854c92
-F src/select.c 35c2b1b4d82190f202887620f99070c0d414c3e030e466032797792cffdbd9f9
+F src/select.c dfc504356e15bb8585d8535a927a72512d1d7a01f9074824964f1781e286231b
 F src/shell.c.in 7d1705f139e6762e8c0fe254a8ebf3ab77aec6d8366f033cdd5f5ebadefbbb20
 F src/sqlite.h.in 100fc660c2f19961b8ed8437b9d53d687de2f8eb2b96437ec6da216adcb643ca
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
@@ -2059,8 +2059,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P dc5bd34963b761c819c565653156d0befbf65cc2cc5dc4113b0ce952450f0352 8036445a36d9d982c1305935e7e37367bdf9e466b923eb6286b52524802e3ccd
-R e6ec32714f5519d3f42f7a87b92d7eba
+P 070634781a5eb41f96b001e48b064e3cd8c82314f576335eb1fcd43792179291
+R 5bcfbb263a340b6c57659d80015cbb33
 U drh
-Z 31a3ccb601c45d898a857131ff2f396b
+Z 28092ed1d737fad311ecc59737148e5d
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-070634781a5eb41f96b001e48b064e3cd8c82314f576335eb1fcd43792179291
+d85bb724fdd6fbad2b88ed7f60e4174e3f65182356f404d04620c5cf6b17f77e

src/select.c

@@ -6654,6 +6654,34 @@ static void printAggInfo(AggInfo *pAggInfo){
 }
 #endif /* TREETRACE_ENABLED */
 
+/*
+** An index on expressions is being used in the inner loop of an
+** aggregate query with a GROUP BY clause.  This routine attempts
+** to adjust the AggInfo object to take advantage of index and to
+** perhaps use the index as a covering index.
+**
+*/
+static int optimizeAggregateUsingIndexedExpr(
+  Parse *pParse,          /* Parsing context */
+  Select *pSelect,        /* The SELECT being coded */
+  AggInfo *pAggInfo       /* The aggregate info */
+){
+#if TREETRACE_ENABLED
+  if( sqlite3TreeTrace & 0x100000 ){
+    IndexedExpr *pIEpr;
+    TREETRACE(0x1000000, pParse, pSelect,
+        ("Attempting to optimize AggInfo for Indexed Exprs\n"));
+    for(pIEpr=pParse->pIdxEpr; pIEpr; pIEpr=pIEpr->pIENext){
+      printf("cur=%d\n", pIEpr->iDataCur);
+      sqlite3TreeViewExpr(0, pIEpr->pExpr, 0);
+    }
+    printAggInfo(pAggInfo);
+  }
+#endif
+  return 0;
+}
+
+
 /*
 ** Generate code for the SELECT statement given in the p argument.  
 **
@@ -7535,6 +7563,9 @@ int sqlite3Select(
         sqlite3ExprListDelete(db, pDistinct);
         goto select_end;
       }
+      if( pParse->pIdxEpr ){
+        optimizeAggregateUsingIndexedExpr(pParse, p, pAggInfo);
+      }
       assignAggregateRegisters(pParse, pAggInfo);
       eDist = sqlite3WhereIsDistinct(pWInfo);
       TREETRACE(0x2,pParse,p,("WhereBegin returns\n"));