From 9b6e83f4b83abcd33c8cf20b95d3e3f4e7a7851a Mon Sep 17 00:00:00 2001
From: unknown <konstantin@mysql.com>
Date: Fri, 7 Apr 2006 22:26:25 +0400
Subject: [PATCH] A fix and a test case for Bug#16248 "WHERE (col1,col2) IN
 ((?,?)) gives wrong results". Implement previously missing Item_row::cleanup.
 The bug is not repeatable in 5.0, probably due to a coincidence: the problem
 is present in 5.0 as well.

mysql-test/r/ps.result:
  Update the result file (Bug#16248)
mysql-test/t/ps.test:
  Add a test case for Bug#16248 "WHERE (col1,col2) IN ((?,?)) gives
  wrong results"
sql/item_row.cc:
  Implement Item_row::cleanup(): we should reset used_tables_cache
  before reexecution of a prepared statement. In case ROW
  arguments contain a placeholder, used_tables_cache has PARAM_TABLE
  bit set in statement prepare. As a result, when executing a statement,
  the condition push down algorithm (make_cond_for_table) would think
  that the WHERE clause belongs to the non-existent PARAM_TABLE and
  wouldn't attach the WHERE clause to any of the real tables,
  effectively optimizing the clause away.
sql/item_row.h:
  Remove a never used member 'array_holder'. Add declaration for
  Item_row::cleanup.
---
 mysql-test/r/ps.result | 20 ++++++++++++++++++++
 mysql-test/t/ps.test   | 18 ++++++++++++++++++
 sql/item_row.cc        | 16 +++++++++++++++-
 sql/item_row.h         |  3 +--
 4 files changed, 54 insertions(+), 3 deletions(-)

diff --git a/mysql-test/r/ps.result b/mysql-test/r/ps.result
index e94c2952893..3f0b9e4fa8b 100644
--- a/mysql-test/r/ps.result
+++ b/mysql-test/r/ps.result
@@ -747,3 +747,23 @@ length(a)
 10
 drop table t1;
 deallocate prepare stmt;
+create table t1 (col1 integer, col2 integer);
+insert into t1 values(100,100),(101,101),(102,102),(103,103);
+prepare stmt from 'select col1, col2 from t1 where (col1, col2) in ((?,?))';
+set @a=100, @b=100;
+execute stmt using @a,@b;
+col1	col2
+100	100
+set @a=101, @b=101;
+execute stmt using @a,@b;
+col1	col2
+101	101
+set @a=102, @b=102;
+execute stmt using @a,@b;
+col1	col2
+102	102
+set @a=102, @b=103;
+execute stmt using @a,@b;
+col1	col2
+deallocate prepare stmt;
+drop table t1;
diff --git a/mysql-test/t/ps.test b/mysql-test/t/ps.test
index af885a5c02f..9b6082eeaf6 100644
--- a/mysql-test/t/ps.test
+++ b/mysql-test/t/ps.test
@@ -785,4 +785,22 @@ select length(a) from t1;
 drop table t1;
 deallocate prepare stmt;
 
+#
+# Bug#16248 "WHERE (col1,col2) IN ((?,?)) gives wrong results":
+# check that ROW implementation is reexecution-friendly.
+#
+create table t1 (col1 integer, col2 integer);
+insert into t1 values(100,100),(101,101),(102,102),(103,103);
+prepare stmt from 'select col1, col2 from t1 where (col1, col2) in ((?,?))';
+set @a=100, @b=100;
+execute stmt using @a,@b;
+set @a=101, @b=101;
+execute stmt using @a,@b;
+set @a=102, @b=102;
+execute stmt using @a,@b;
+set @a=102, @b=103;
+execute stmt using @a,@b;
+deallocate prepare stmt;
+drop table t1;
+
 # End of 4.1 tests
diff --git a/sql/item_row.cc b/sql/item_row.cc
index 12d202a1699..493eefc9ff0 100644
--- a/sql/item_row.cc
+++ b/sql/item_row.cc
@@ -26,7 +26,7 @@
 */
 
 Item_row::Item_row(List<Item> &arg):
-  Item(), used_tables_cache(0), array_holder(1), const_item_cache(1), with_null(0)
+  Item(), used_tables_cache(0), const_item_cache(1), with_null(0)
 {
 
   //TODO: think placing 2-3 component items in item (as it done for function)
@@ -85,6 +85,20 @@ bool Item_row::fix_fields(THD *thd, TABLE_LIST *tabl, Item **ref)
 }
 
 
+void Item_row::cleanup()
+{
+  DBUG_ENTER("Item_row::cleanup");
+
+  Item::cleanup();
+  /* Reset to the original values */
+  used_tables_cache= 0;
+  const_item_cache= 1;
+  with_null= 0;
+
+  DBUG_VOID_RETURN;
+}
+
+
 void Item_row::split_sum_func(THD *thd, Item **ref_pointer_array,
                               List<Item> &fields)
 {
diff --git a/sql/item_row.h b/sql/item_row.h
index 39bc4513e1e..28cb47b6815 100644
--- a/sql/item_row.h
+++ b/sql/item_row.h
@@ -19,7 +19,6 @@ class Item_row: public Item
   Item **items;
   table_map used_tables_cache;
   uint arg_count;
-  bool array_holder;
   bool const_item_cache;
   bool with_null;
 public:
@@ -29,7 +28,6 @@ public:
     items(item->items),
     used_tables_cache(item->used_tables_cache),
     arg_count(item->arg_count),
-    array_holder(0), 
     const_item_cache(item->const_item_cache),
     with_null(0)
   {}
@@ -57,6 +55,7 @@ public:
     return 0;
   };
   bool fix_fields(THD *thd, TABLE_LIST *tables, Item **ref);
+  void cleanup();
   void split_sum_func(THD *thd, Item **ref_pointer_array, List<Item> &fields);
   table_map used_tables() const { return used_tables_cache; };
   bool const_item() const { return const_item_cache; };