3 files changed, 37 insertions, 0 deletions
diff --git a/mysql-test/t/ps.test b/mysql-test/t/ps.test
index 22d0abf645e..645538ee890 100644
--- a/mysql-test/t/ps.test
+++ b/mysql-test/t/ps.test
@@ -870,6 +870,36 @@ drop table t1;
 set names default;
 deallocate prepare stmt;
 
+#
+# A test case for Bug#12734 "prepared statement may return incorrect result
+# set for a select SQL request": test that canDoTurboBM is reset for each
+# execute of a prepared statement.
+#
+create table t1 (
+  word_id mediumint(8) unsigned not null default '0',
+  formatted varchar(20) not null default ''
+);
+
+insert into t1 values
+  (80,'pendant'), (475,'pretendants'), (989,'tendances'),
+  (1019,'cependant'),(1022,'abondance'),(1205,'independants'),
+  (13,'lessiver'),(25,'lambiner'),(46,'situer'),(71,'terminer'),
+  (82,'decrocher');
+
+select count(*) from t1 where formatted like '%NDAN%';
+select count(*) from t1 where formatted like '%ER';
+prepare stmt from "select count(*) from t1 where formatted like ?";
+set @like="%NDAN%";
+execute stmt using @like;
+set @like="%ER";
+execute stmt using @like;
+set @like="%NDAN%";
+execute stmt using @like;
+set @like="%ER";
+execute stmt using @like;
+deallocate prepare stmt;
+drop table t1;
+
 # End of 4.1 tests
 
 #
diff --git a/sql/item_cmpfunc.cc b/sql/item_cmpfunc.cc
index 306277aa438..bb3f6e8b231 100644
--- a/sql/item_cmpfunc.cc
+++ b/sql/item_cmpfunc.cc
@@ -3059,6 +3059,12 @@ bool Item_func_like::fix_fields(THD *thd, Item **ref)
   return FALSE;
 }
 
+void Item_func_like::cleanup()
+{
+  canDoTurboBM= FALSE;
+  Item_bool_func2::cleanup();
+}
+
 #ifdef USE_REGEX
 
 bool
diff --git a/sql/item_cmpfunc.h b/sql/item_cmpfunc.h
index 98ccefd08ab..15aebd2492c 100644
--- a/sql/item_cmpfunc.h
+++ b/sql/item_cmpfunc.h
@@ -1001,6 +1001,7 @@ public:
   cond_result eq_cmp_result() const { return COND_TRUE; }
   const char *func_name() const { return "like"; }
   bool fix_fields(THD *thd, Item **ref);
+  void cleanup();
 };
 
 #ifdef USE_REGEX