From c394dbe14ad17d2ede6d3fd9dfa8cd2b205a427d Mon Sep 17 00:00:00 2001
From: "igor@olga.mysql.com" <>
Date: Fri, 7 Dec 2007 17:14:59 -0800
Subject: [PATCH] Fixed bug #32815. The index (key_part_1, key_part-2) was
 erroneously considered as compatible with the required ordering in the
 function test_test_if_order_by_key when a query with an ORDER BY clause
 contained a condition of the form   key_part_1=const OR key_part_1 IS NULL
 and the order list contained only key_part_2. This happened because the value
 of the const_key_parts field in the KEYUSE structure was not formed correctly
 for the keys that could be used for ref_or_null access. This was fixed in the
 code of the update_ref_and_keys function. The problem could not manifest
 itself for MyISAM databases because the implementation of the
 keys_to_use_for_scanning() handler function always returns an empty bitmap
 for the MyISAM engine.

---
 mysql-test/r/innodb_mysql.result | 12 ++++++++++++
 mysql-test/t/innodb_mysql.test   | 15 +++++++++++++++
 sql/sql_select.cc                |  2 +-
 3 files changed, 28 insertions(+), 1 deletion(-)

diff --git a/mysql-test/r/innodb_mysql.result b/mysql-test/r/innodb_mysql.result
index b073e4bd6ce..7450d8c349b 100644
--- a/mysql-test/r/innodb_mysql.result
+++ b/mysql-test/r/innodb_mysql.result
@@ -1213,4 +1213,16 @@ a	b
 3	2
 1	1
 DROP TABLE t1;
+CREATE TABLE t1 (id int, type char(6), d int, INDEX idx(id,d)) ENGINE=InnoDB;
+INSERT INTO t1 VALUES 
+(191, 'member', 1), (NULL, 'member', 3), (NULL, 'member', 4), (201, 'member', 2);
+EXPLAIN SELECT * FROM t1 WHERE id=191 OR id IS NULL ORDER BY d;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	idx	NULL	NULL	NULL	3	Using where; Using filesort
+SELECT * FROM t1 WHERE id=191 OR id IS NULL ORDER BY d;
+id	type	d
+191	member	1
+NULL	member	3
+NULL	member	4
+DROP TABLE t1;
 End of 5.0 tests
diff --git a/mysql-test/t/innodb_mysql.test b/mysql-test/t/innodb_mysql.test
index f64efd600c5..f1b15d05a60 100644
--- a/mysql-test/t/innodb_mysql.test
+++ b/mysql-test/t/innodb_mysql.test
@@ -960,4 +960,19 @@ SELECT * FROM t1 ORDER BY b DESC, a ASC;
 
 DROP TABLE t1;
 
+#
+# Bug #32815: query with ORDER BY and a possible ref_or_null access
+#
+
+CREATE TABLE t1 (id int, type char(6), d int, INDEX idx(id,d)) ENGINE=InnoDB;
+INSERT INTO t1 VALUES 
+  (191, 'member', 1), (NULL, 'member', 3), (NULL, 'member', 4), (201, 'member', 2); 
+
+EXPLAIN SELECT * FROM t1 WHERE id=191 OR id IS NULL ORDER BY d;
+SELECT * FROM t1 WHERE id=191 OR id IS NULL ORDER BY d;
+
+DROP TABLE t1;
+
+
+
 --echo End of 5.0 tests
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index bcf538cdde2..d1bd018878a 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -3691,7 +3691,7 @@ update_ref_and_keys(THD *thd, DYNAMIC_ARRAY *keyuse,JOIN_TAB *join_tab,
     found_eq_constant=0;
     for (i=0 ; i < keyuse->elements-1 ; i++,use++)
     {
-      if (!use->used_tables)
+      if (!use->used_tables && use->optimize != KEY_OPTIMIZE_REF_OR_NULL)
 	use->table->const_key_parts[use->key]|= use->keypart_map;
       if (use->keypart != FT_KEYPART)
       {