From 05ae989e76aaab49537ac8b83ed8358be0476991 Mon Sep 17 00:00:00 2001
From: Sergey Petrunia <sergefp@mysql.com>
Date: Fri, 19 Dec 2008 16:38:39 +0300
Subject: [PATCH] BUG#40974: Incorrect query results when using clause
 evaluated using range check - QUICK_INDEX_MERGE_SELECT deinitializes its
 rnd_pos() scan when it reaches EOF, but we   need to make the
 deinitialization in QUICK_INDEX_MERGE_SELECT destructor also. This is because
   certain execution strategies can stop scanning without reaching EOF, then
 then try to do a full   table scan on this table. Failure to deinitialize
 caused the full scan to use (already empty)   table->sort and produce zero
 records.

---
 mysql-test/r/index_merge.result | 28 ++++++++++++++++++++++++++++
 mysql-test/t/index_merge.test   | 26 ++++++++++++++++++++++++++
 sql/opt_range.cc                |  3 +++
 3 files changed, 57 insertions(+)

diff --git a/mysql-test/r/index_merge.result b/mysql-test/r/index_merge.result
index ed397e8fdc8..f3fce29c910 100644
--- a/mysql-test/r/index_merge.result
+++ b/mysql-test/r/index_merge.result
@@ -527,4 +527,32 @@ b	a
 	y
 	z
 DROP TABLE t1;
+#
+# BUG#40974: Incorrect query results when using clause evaluated using range check
+#
+create table t0 (a int);
+insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
+create table t1 (a int);
+insert into t1 values (1),(2);
+create table t2(a int, b int);
+insert into t2 values (1,1), (2, 1000);
+create table t3 (a int, b int, filler char(100), key(a), key(b));
+insert into t3 select 1000, 1000,'filler' from t0 A, t0 B, t0 C;
+insert into t3 values (1,1,'data');
+insert into t3 values (1,1,'data');
+The plan should be ALL/ALL/ALL(Range checked for each record (index map: 0x3)
+explain select * from t1 
+where exists (select 1 from t2, t3 
+where t2.a=t1.a and (t3.a=t2.b or t3.b=t2.b or t3.b=t2.b+1));
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
+2	DEPENDENT SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	2	Using where
+2	DEPENDENT SUBQUERY	t3	ALL	a,b	NULL	NULL	NULL	1002	Range checked for each record (index map: 0x3)
+select * from t1 
+where exists (select 1 from t2, t3 
+where t2.a=t1.a and (t3.a=t2.b or t3.b=t2.b or t3.b=t2.b+1));
+a
+1
+2
+drop table t0, t1, t2, t3;
 End of 5.0 tests
diff --git a/mysql-test/t/index_merge.test b/mysql-test/t/index_merge.test
index 970b9a87454..7f176a4cd11 100644
--- a/mysql-test/t/index_merge.test
+++ b/mysql-test/t/index_merge.test
@@ -477,4 +477,30 @@ SELECT b,a from t1 WHERE (b!='c' AND b!='f' && b!='h') OR
 
 DROP TABLE t1;
 
+--echo #
+--echo # BUG#40974: Incorrect query results when using clause evaluated using range check
+--echo #
+create table t0 (a int);
+insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
+
+create table t1 (a int);
+insert into t1 values (1),(2);
+create table t2(a int, b int);
+insert into t2 values (1,1), (2, 1000);
+create table t3 (a int, b int, filler char(100), key(a), key(b));
+
+insert into t3 select 1000, 1000,'filler' from t0 A, t0 B, t0 C; 
+insert into t3 values (1,1,'data');
+insert into t3 values (1,1,'data');
+-- echo The plan should be ALL/ALL/ALL(Range checked for each record (index map: 0x3)
+explain select * from t1 
+where exists (select 1 from t2, t3 
+              where t2.a=t1.a and (t3.a=t2.b or t3.b=t2.b or t3.b=t2.b+1));
+
+select * from t1 
+where exists (select 1 from t2, t3 
+              where t2.a=t1.a and (t3.a=t2.b or t3.b=t2.b or t3.b=t2.b+1));
+
+drop table t0, t1, t2, t3;
+
 --echo End of 5.0 tests
diff --git a/sql/opt_range.cc b/sql/opt_range.cc
index 204ebdb6f33..744415fa2fe 100644
--- a/sql/opt_range.cc
+++ b/sql/opt_range.cc
@@ -1109,6 +1109,9 @@ QUICK_INDEX_MERGE_SELECT::~QUICK_INDEX_MERGE_SELECT()
     quick->file= NULL;
   quick_selects.delete_elements();
   delete pk_quick_select;
+  /* It's ok to call the next two even if they are already deinitialized */
+  end_read_record(&read_record);
+  free_io_cache(head);
   free_root(&alloc,MYF(0));
   DBUG_VOID_RETURN;
 }