From: drh <>
Date: Thu, 24 Nov 2022 01:40:20 +0000 (+0000)
Subject: Add explanatory comment to the new optimization.  And add a test case.
X-Git-Tag: version-3.41.0~372^2~9
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=9b80cb5f39af66075762057df127ffbbb2c6ef2a;p=thirdparty%2Fsqlite.git

Add explanatory comment to the new optimization.  And add a test case.

FossilOrigin-Name: e6c20f61de7d048eee65c8e74a3eb36760ab9747ebd1ab50e49642b777c10306
---

diff --git a/manifest b/manifest
index 5a5586e90e..9476f82d3e 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Aggregates\swith\sGROUP\sBY\snow\smake\suse\sof\sexpressions\son\sindexes.\s\sThis\scode\nworks\sand\sgets\sthe\scorrect\sanswer\sfor\sthe\stest\scase\sin\sthe\sticket.\s\sLots\smore\ntesting\sand\sdocumentation\sis\sneeded,\showever.
-D 2022-11-23T18:51:04.363
+C Add\sexplanatory\scomment\sto\sthe\snew\soptimization.\s\sAnd\sadd\sa\stest\scase.
+D 2022-11-24T01:40:20.262
 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 f253214cbd2458f744b95fc6bf8dee103cecf4b051f620fd5f62b43dbab92ec1
+F src/select.c 7fcbbc0db92d0082e3a10b4492457932d8589e9027e843ac2b972a4ba0233136
 F src/shell.c.in 7d1705f139e6762e8c0fe254a8ebf3ab77aec6d8366f033cdd5f5ebadefbbb20
 F src/sqlite.h.in 100fc660c2f19961b8ed8437b9d53d687de2f8eb2b96437ec6da216adcb643ca
 F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
@@ -1628,6 +1628,7 @@ F test/tkt-868145d012.test a5f941107ece6a64410ca4755c6329b7eb57a356
 F test/tkt-8c63ff0ec.test 258b7fc8d7e4e1cb5362c7d65c143528b9c4cbed
 F test/tkt-91e2e8ba6f.test 08c4f94ae07696b05c9b822da0b4e5337a2f54c5
 F test/tkt-94c04eaadb.test f738c57c7f68ab8be1c054415af7774617cb6223
+F test/tkt-99378177930f87bd.test f33bf2e038025941eb2f5495db4d4e3f5a614cdf6c44e0fe4d420d41197330c1
 F test/tkt-9a8b09f8e6.test b2ef151d0984b2ebf237760dbeaa50724e5a0667
 F test/tkt-9d68c883.test 16f7cb96781ba579bc2e19bb14b4ad609d9774b6
 F test/tkt-9f2eb3abac.test cb6123ac695a08b4454c3792fbe85108f67fabf8
@@ -2059,8 +2060,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 84c06023f4a1606664fdb9811312603b31f7c94a43d0e443ba7dde7fdba029e3
-R 2344df85f68d9987b55d50d38bac47c1
+P 8dcf9f2031c16f296d187fe876d4204c71fc96fec120984ff11b6d8b03d58a5f
+R 9274a8d11a500d33c0e780bbd7f350f0
 U drh
-Z 4c924f435822db601e489fbe4dcd4a9e
+Z b2115b9d996407ff47bc262d3bc9ad3e
 # Remove this line to create a well-formed Fossil manifest.
diff --git a/manifest.uuid b/manifest.uuid
index 56c84edce5..cdcf19b4bf 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-8dcf9f2031c16f296d187fe876d4204c71fc96fec120984ff11b6d8b03d58a5f
\ No newline at end of file
+e6c20f61de7d048eee65c8e74a3eb36760ab9747ebd1ab50e49642b777c10306
\ No newline at end of file
diff --git a/src/select.c b/src/select.c
index dcb878dde9..dcf899e4bb 100644
--- a/src/select.c
+++ b/src/select.c
@@ -7703,6 +7703,11 @@ int sqlite3Select(
         pAggInfo->useSortingIdx = 1;
       }
 
+      /* If there entries in pAgggInfo->aFunc[] that contain subexpressions
+      ** that are indexed (and that were previously identified and tagged
+      ** in optimizeAggregateUseOfIndexedExpr()) then those subexpressions
+      ** must now be converted into a TK_AGG_COLUMN node so that the value
+      ** is correctly pulled from the index rather than being recomputed. */
       if( pParse->pIdxEpr ){
         aggregateConvertIndexedExprRefToColumn(pAggInfo);
 #if TREETRACE_ENABLED
diff --git a/test/tkt-99378177930f87bd.test b/test/tkt-99378177930f87bd.test
new file mode 100644
index 0000000000..aad0a6dc21
--- /dev/null
+++ b/test/tkt-99378177930f87bd.test
@@ -0,0 +1,69 @@
+# 2022-11-23
+#
+# The author disclaims copyright to this source code.  In place of
+# a legal notice, here is a blessing:
+#
+#    May you do good and not evil.
+#    May you find forgiveness for yourself and forgive others.
+#    May you share freely, never taking more than you give.
+#
+#***********************************************************************
+# This file implements regression tests for SQLite library.
+#
+# This file implements tests to verify that the enhancement
+# request documented by ticket 99378177930f87bd is working.
+#
+# The enhancement is that if an aggregate query with a GROUP BY clause
+# uses subexpressions in the arguments to aggregate functions that are
+# also columns of an index, then the values are pulled from the index
+# rather than being recomputed.  This has the potential to make some
+# indexed queries works as if the index were covering.
+#
+
+set testdir [file dirname $argv0]
+source $testdir/tester.tcl
+
+do_execsql_test tkt-99378-100 {
+  CREATE TABLE t1(a INT, b TEXT, c INT, d INT);
+  INSERT INTO t1(a,b,c,d) VALUES
+    (1, '{"x":1}', 12,  3),
+    (1, '{"x":2}',  4,  5),
+    (1, '{"x":1}',  6, 11),
+    (2, '{"x":1}', 22,  3),
+    (2, '{"x":2}',  4,  5),
+    (3, '{"x":1}',  6,  7);
+  CREATE INDEX t1x ON t1(d, a, b->>'x', c);
+} {}
+do_execsql_test tkt-99378-110 {
+  SELECT a,
+         SUM(1)                              AS t1,
+         SUM(CASE WHEN b->>'x'=1 THEN 1 END) AS t2,
+         SUM(c)                              AS t3,
+         SUM(CASE WHEN b->>'x'=1 THEN c END) AS t4
+    FROM t1
+   WHERE d BETWEEN 0 and 10
+   GROUP BY a;
+} {
+  1  2  1 16 12
+  2  2  1 26 22
+  3  1  1  6  6
+}
+
+# The proof that the index on the expression is being used is in the
+# fact that the byte code contains no "Function" opcodes.  In other words,
+# the ->> operator (which is implemented by a function) is never invoked.
+# Instead, the b->>'x' value is pulled out of the index.
+#
+do_execsql_test tkt-99378-120 {
+  EXPLAIN
+  SELECT a,
+         SUM(1)                              AS t1,
+         SUM(CASE WHEN b->>'x'=1 THEN 1 END) AS t2,
+         SUM(c)                              AS t3,
+         SUM(CASE WHEN b->>'x'=1 THEN c END) AS t4
+    FROM t1
+   WHERE d BETWEEN 0 and 10
+   GROUP BY a;
+} {~/Function/}
+
+finish_test