From 9e6f484788db461b46a365d415ee7043cab65f1e Mon Sep 17 00:00:00 2001
From: Igor Babaev <igor@askmonty.org>
Date: Thu, 13 Oct 2011 22:39:00 -0700
Subject: [PATCH] Fixed LP bug #872735. This bug happened because the maps of
 covering keys for mergeable derived tables/views was not recalculated after
 the derived tables/vies had been merged into the main query.

---
 mysql-test/r/derived_view.result | 38 ++++++++++++++++++++++++++++++++
 mysql-test/t/derived_view.test   | 33 +++++++++++++++++++++++++++
 sql/item.h                       |  5 +++++
 sql/sql_lex.cc                   | 15 +++++++++++++
 4 files changed, 91 insertions(+)

diff --git a/mysql-test/r/derived_view.result b/mysql-test/r/derived_view.result
index b79485d94e0..ceb63ddc967 100644
--- a/mysql-test/r/derived_view.result
+++ b/mysql-test/r/derived_view.result
@@ -1424,4 +1424,42 @@ a	a	c	a	a	c	b	a	d
 6	23	-1	NULL	NULL	NULL	NULL	NULL	5
 DROP VIEW v2,v3;
 DROP TABLE t1,t2,t3,t4,t5;
+#
+# LP bug #872735: derived used in a NOT IN subquery
+#                 
+CREATE TABLE t1 (b int NOT NULL);
+INSERT INTO t1 VALUES (9), (7);
+CREATE TABLE t2 (a int NOT NULL) ;
+INSERT INTO t2 VALUES (1), (2);
+CREATE TABLE t3 (
+a int NOT NULL , c int NOT NULL, d varchar(1) NOT NULL, 
+KEY (c,a) , PRIMARY KEY (a)
+);
+INSERT INTO t3 VALUES
+(14,4,'a'), (15,7,'b'), (16,4,'c'), (17,1,'d'), (18,9,'e'),
+(19,4,'f'), (20,8,'g');
+SET SESSION optimizer_switch='derived_merge=on,subquery_cache=off';
+# The following two EXPLAINs must return the same execution plan
+EXPLAIN
+SELECT * FROM t1 , t2
+WHERE (t2.a ,t1.b) NOT IN (SELECT DISTINCT c,a  FROM t3 t);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	2	Using where; Using join buffer (flat, BNL join)
+2	DEPENDENT SUBQUERY	t	ref	PRIMARY,c	c	4	func	2	Using where; Using index
+EXPLAIN 
+SELECT * FROM t1 , t2
+WHERE (t2.a ,t1.b) NOT IN (SELECT DISTINCT c,a  FROM (SELECT * FROM t3) t);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	2	Using where; Using join buffer (flat, BNL join)
+2	DEPENDENT SUBQUERY	t3	ref	PRIMARY,c	c	4	func	2	Using where; Using index
+SELECT * FROM t1 , t2
+WHERE (t2.a ,t1.b) NOT IN (SELECT DISTINCT c,a  FROM (SELECT * FROM t3) t);
+b	a
+9	1
+7	1
+9	2
+7	2
+DROP TABLE t1,t2,t3;
 set optimizer_switch=@exit_optimizer_switch;
diff --git a/mysql-test/t/derived_view.test b/mysql-test/t/derived_view.test
index 1c8cbec8a3e..9f7e24481a0 100644
--- a/mysql-test/t/derived_view.test
+++ b/mysql-test/t/derived_view.test
@@ -877,5 +877,38 @@ SELECT STRAIGHT_JOIN *
 DROP VIEW v2,v3;
 DROP TABLE t1,t2,t3,t4,t5;
 
+--echo #
+--echo # LP bug #872735: derived used in a NOT IN subquery
+--echo #                 
+
+CREATE TABLE t1 (b int NOT NULL);
+INSERT INTO t1 VALUES (9), (7);
+
+CREATE TABLE t2 (a int NOT NULL) ;
+INSERT INTO t2 VALUES (1), (2);
+
+CREATE TABLE t3 (
+  a int NOT NULL , c int NOT NULL, d varchar(1) NOT NULL, 
+  KEY (c,a) , PRIMARY KEY (a)
+);
+INSERT INTO t3 VALUES
+  (14,4,'a'), (15,7,'b'), (16,4,'c'), (17,1,'d'), (18,9,'e'),
+  (19,4,'f'), (20,8,'g');
+
+SET SESSION optimizer_switch='derived_merge=on,subquery_cache=off';
+
+--echo # The following two EXPLAINs must return the same execution plan
+EXPLAIN
+SELECT * FROM t1 , t2
+  WHERE (t2.a ,t1.b) NOT IN (SELECT DISTINCT c,a  FROM t3 t);
+EXPLAIN 
+SELECT * FROM t1 , t2
+  WHERE (t2.a ,t1.b) NOT IN (SELECT DISTINCT c,a  FROM (SELECT * FROM t3) t);
+
+SELECT * FROM t1 , t2
+  WHERE (t2.a ,t1.b) NOT IN (SELECT DISTINCT c,a  FROM (SELECT * FROM t3) t);
+
+DROP TABLE t1,t2,t3;
+
 # The following command must be the last one the file 
 set optimizer_switch=@exit_optimizer_switch;
diff --git a/sql/item.h b/sql/item.h
index 8cacd231fbf..efd358db874 100644
--- a/sql/item.h
+++ b/sql/item.h
@@ -1816,6 +1816,11 @@ public:
   bool get_date_result(MYSQL_TIME *ltime,uint fuzzydate);
   bool is_null() { return field->is_null(); }
   void update_null_value();
+  void update_used_tables() 
+  {
+    if (field && field->table)
+      field->table->covering_keys.intersect(field->part_of_key);
+  }
   Item *get_tmp_table_item(THD *thd);
   bool collect_item_field_processor(uchar * arg);
   bool add_field_to_set_processor(uchar * arg);
diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
index 7f39d4ad7f3..64e295d82ea 100644
--- a/sql/sql_lex.cc
+++ b/sql/sql_lex.cc
@@ -3411,6 +3411,21 @@ void SELECT_LEX::update_used_tables()
   while ((tl= ti++))
   {
     TABLE_LIST *embedding;
+    if (tl->table)
+    {
+      embedding= tl->embedding;
+      for (embedding= tl->embedding; embedding; embedding=embedding->embedding)
+      {
+        if (embedding->is_view_or_derived())
+	{
+          DBUG_ASSERT(embedding->is_merged_derived());
+          TABLE *tab= tl->table;
+          tab->covering_keys= tab->s->keys_for_keyread;
+          tab->covering_keys.intersect(tab->keys_in_use_for_query);
+          break;
+        }
+      }
+    }
     embedding= tl;
     do
     {