Add VM code comments on the group-by processing. Extra group-by test case. (CVS 2731)

FossilOrigin-Name: 655e75ac7d96b05c118226c5b70443da2df319ec

manifest

@@ -1,5 +1,5 @@
-C Code\scleanup\sand\ssimplification.\s\sThree\snew\sMem\sopcodes\sadded.\nThe\ssqlite3VdbeJumpHere\sfunction\sadded.\s(CVS\s2730)
+C Add\sVM\scode\scomments\son\sthe\sgroup-by\sprocessing.\s\sExtra\sgroup-by\stest\scase.\s(CVS\s2731)
-D 2005-09-20T17:42:23
+D 2005-09-20T18:13:24
 F Makefile.in 12784cdce5ffc8dfb707300c34e4f1eb3b8a14f1
 F Makefile.linux-gcc 06be33b2a9ad4f005a5f42b22c4a19dab3cbb5c7
 F README 9c4e2d6706bdcc3efdd773ce752a8cdab4f90028
@@ -63,7 +63,7 @@ F src/pragma.c 126149668aa7086e86cfa3e32c8523513c19dd63
 F src/prepare.c fc098db25d2a121affb08686cf04833fd50452d4
 F src/printf.c bd421c1ad5e01013c89af63c60eab02852ccd15e
 F src/random.c 90adff4e73a3b249eb4f1fc2a6ff9cf78c7233a4
-F src/select.c 240f456bc85e60e21b9d16a4b1ac09d6266b340f
+F src/select.c 034c7f7447b8711f85bef578a437ea12ca7cac53
 F src/shell.c 3596c1e559b82663057940d19ba533ad421c7dd3
 F src/sqlite.h.in 461b2535550cf77aedfd44385da11ef7d63e57a2
 F src/sqliteInt.h 53daa72541b4336c5e89773cf39717ed695bd523
@@ -203,7 +203,7 @@ F test/select1.test 480233d4f5a81d7d59a55e40d05084d97e57ecdf
 F test/select2.test f3c2678c3a9f3cf08ec4988a3845bda64be6d9e3
 F test/select3.test 576df1a5cc5e01dadae9176384e2d506315afdcf
 F test/select4.test c239f516aa31f42f2ef7c6d7cd01105f08f934ca
-F test/select5.test 93323dd60ea8dfe2c5fee86644279dee5ad5ea23
+F test/select5.test 07a90ab3c7e3f0a241a9cdea1d997b2c8a89ff0b
 F test/select6.test 21b72c56e7cbcefd063fdf9bc6c89342aedabccf
 F test/select7.test 1bf795b948c133a15a2a5e99d3270e652ec58ce6
 F test/sort.test 0c33a8ae1c238377ad197387c3872175f40d3843
@@ -311,7 +311,7 @@ F www/tclsqlite.tcl ddcf912ea48695603c8ed7efb29f0812ef8d1b49
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl a99cf5f6d8bd4d5537584a2b342f0fb9fa601d8b
 F www/whentouse.tcl 97e2b5cd296f7d8057e11f44427dea8a4c2db513
-P f22d0f64a0b9100e16746fb800efa508d286e40e
+P 2471957feee57538e5e1e50a704a337f0927d10e
-R 3effef3e7ca21a06e1bfa94b9c1adaf9
+R fbbb91149671f932014d08503073584b
 U drh
-Z 30993b6d59068461f41957a47370eeb7
+Z 29eed70ee2810d17c2933c512e93e023

manifest.uuid

@@ -1 +1 @@
-2471957feee57538e5e1e50a704a337f0927d10e
+655e75ac7d96b05c118226c5b70443da2df319ec

src/select.c

@@ -12,7 +12,7 @@
 ** This file contains C code routines that are called by the parser
 ** to handle SELECT statements in SQLite.
 **
-** $Id: select.c,v 1.275 2005/09/20 17:42:23 drh Exp $
+** $Id: select.c,v 1.276 2005/09/20 18:13:24 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -2915,8 +2915,9 @@ int sqlite3Select(
       iBMem = pParse->nMem;
       pParse->nMem += pGroupBy->nExpr;
       sqlite3VdbeAddOp(v, OP_MemInt, 0, iAbortFlag);
+      VdbeComment((v, "# clear abort flag"));
       sqlite3VdbeAddOp(v, OP_MemInt, 0, iUseFlag);
-      sqlite3VdbeAddOp(v, OP_MemNull, iAMem, 0);
+      VdbeComment((v, "# indicate accumulator empty"));
       sqlite3VdbeAddOp(v, OP_Goto, 0, addrInitializeLoop);
 
       /* Generate a subroutine that outputs a single row of the result
@@ -2927,10 +2928,12 @@ int sqlite3Select(
       ** order to signal the caller to abort.
       */
       addrSetAbort = sqlite3VdbeCurrentAddr(v);
-      sqlite3VdbeAddOp(v, OP_MemIncr, iAbortFlag, 0);
+      sqlite3VdbeAddOp(v, OP_MemInt, 1, iAbortFlag);
+      VdbeComment((v, "# set abort flag"));
       sqlite3VdbeAddOp(v, OP_Return, 0, 0);
       addrOutputRow = sqlite3VdbeCurrentAddr(v);
       sqlite3VdbeAddOp(v, OP_IfMemPos, iUseFlag, addrOutputRow+2);
+      VdbeComment((v, "# Groupby result generator entry point"));
       sqlite3VdbeAddOp(v, OP_Return, 0, 0);
       finalizeAggFunctions(pParse, &sAggInfo);
       if( pHaving ){
@@ -2943,6 +2946,7 @@ int sqlite3Select(
         goto select_end;
       }
       sqlite3VdbeAddOp(v, OP_Return, 0, 0);
+      VdbeComment((v, "# end groupby result generator"));
 
       /* Generate a subroutine that will reset the group-by accumulator
       */
@@ -2990,6 +2994,7 @@ int sqlite3Select(
         sqlite3VdbeAddOp(v, OP_IdxInsert, sAggInfo.sortingIdx, 0);
         sqlite3WhereEnd(pWInfo);
         sqlite3VdbeAddOp(v, OP_Sort, sAggInfo.sortingIdx, addrEnd);
+        VdbeComment((v, "# GROUP BY sort"));
         sAggInfo.useSortingIdx = 1;
       }
 
@@ -3035,15 +3040,19 @@ int sqlite3Select(
         sqlite3VdbeAddOp(v, OP_MemMove, iAMem+j, iBMem+j);
       }
       sqlite3VdbeAddOp(v, OP_Gosub, 0, addrOutputRow);
+      VdbeComment((v, "# output one row"));
       sqlite3VdbeAddOp(v, OP_IfMemPos, iAbortFlag, addrEnd);
+      VdbeComment((v, "# check abort flag"));
       sqlite3VdbeAddOp(v, OP_Gosub, 0, addrReset);
+      VdbeComment((v, "# reset accumulator"));
 
       /* Update the aggregate accumulators based on the content of
       ** the current row
       */
       sqlite3VdbeResolveLabel(v, addrProcessRow);
       updateAccumulator(pParse, &sAggInfo);
-      sqlite3VdbeAddOp(v, OP_MemIncr, iUseFlag, 0);
+      sqlite3VdbeAddOp(v, OP_MemInt, 1, iUseFlag);
+      VdbeComment((v, "# indicate data in accumulator"));
 
       /* End of the loop
       */
@@ -3057,6 +3066,7 @@ int sqlite3Select(
       /* Output the final row of result
       */
       sqlite3VdbeAddOp(v, OP_Gosub, 0, addrOutputRow);
+      VdbeComment((v, "# output final row"));
       
     } /* endif pGroupBy */
     else {

test/select5.test

@@ -12,7 +12,7 @@
 # focus of this file is testing aggregate functions and the
 # GROUP BY and HAVING clauses of SELECT statements.
 #
-# $Id: select5.test,v 1.14 2005/09/20 13:12:00 drh Exp $
+# $Id: select5.test,v 1.15 2005/09/20 18:13:25 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -168,5 +168,19 @@ do_test select5-6.1 {
     SELECT count(x), y FROM t3 GROUP BY y ORDER BY 1
   }
 } {1 4 2 {}}
+do_test select5-6.2 {
+  execsql {
+    CREATE TABLE t4(x,y,z);
+    INSERT INTO t4 VALUES(1,2,NULL);
+    INSERT INTO t4 VALUES(2,3,NULL);
+    INSERT INTO t4 VALUES(3,NULL,5);
+    INSERT INTO t4 VALUES(4,NULL,6);
+    INSERT INTO t4 VALUES(4,NULL,6);
+    INSERT INTO t4 VALUES(5,NULL,NULL);
+    INSERT INTO t4 VALUES(5,NULL,NULL);
+    INSERT INTO t4 VALUES(6,7,8);
+    SELECT max(x), count(x), y, z FROM t4 GROUP BY y, z ORDER BY 1
+  }
+} {1 1 2 {} 2 1 3 {} 3 1 {} 5 4 2 {} 6 5 2 {} {} 6 1 7 8}
   
 finish_test