Fix for BUG#20550: Stored function: wrong RETURN type metadata

when used in a VIEW.

The problem was that wrong function (create_tmp_from_item())
was used to create a temporary field for Item_func_sp.

The fix is to use create_tmp_from_field().


mysql-test/r/sp.result:
  Update result file.
mysql-test/t/sp.test:
  Add a test case for BUG#20550.
sql/item_func.h:
  Add a getter for Item_func_sp::sp_result_field.
sql/sql_select.cc:
  Use create_tmp_from_field() to create a temporary field
  for Item_func_sp.

mysql-test/r/sp.result

@@ -4914,7 +4914,7 @@ create table t3 as select * from v1|
 show create table t3|
 Table	Create Table
 t3	CREATE TABLE `t3` (
-  `j` bigint(11) DEFAULT NULL
+  `j` int(11) DEFAULT NULL
 ) ENGINE=MyISAM DEFAULT CHARSET=latin1
 select * from t3|
 j
@@ -6599,3 +6599,51 @@ DROP TABLE t1;
 DROP PROCEDURE p1;
 DROP PROCEDURE p2;
 End of 5.0 tests
+
+#
+# Bug#20550.
+#
+
+#
+# - Prepare.
+#
+
+DROP VIEW IF EXISTS v1;
+DROP VIEW IF EXISTS v2;
+DROP FUNCTION IF EXISTS f1;
+DROP FUNCTION IF EXISTS f2;
+
+#
+# - Create required objects.
+#
+
+CREATE FUNCTION f1() RETURNS VARCHAR(65525) RETURN 'Hello';
+
+CREATE FUNCTION f2() RETURNS TINYINT RETURN 1;
+
+CREATE VIEW v1 AS SELECT f1();
+
+CREATE VIEW v2 AS SELECT f2();
+
+#
+# - Check.
+#
+
+SELECT DATA_TYPE FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'v1';
+DATA_TYPE
+varchar
+
+SELECT DATA_TYPE FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'v2';
+DATA_TYPE
+tinyint
+
+#
+# - Cleanup.
+#
+
+DROP FUNCTION f1;
+DROP FUNCTION f2;
+DROP VIEW v1;
+DROP VIEW v2;
+
+End of 5.1 tests

mysql-test/t/sp.test

@@ -7549,3 +7549,87 @@ DROP PROCEDURE p1;
 DROP PROCEDURE p2;
 
 --echo End of 5.0 tests
+
+###########################################################################
+
+#
+# Bug#20550: Stored function: wrong RETURN type metadata when used in a VIEW.
+#
+
+###########################################################################
+
+--echo
+
+--echo #
+--echo # Bug#20550.
+--echo #
+
+--echo
+
+--echo #
+--echo # - Prepare.
+--echo #
+
+--echo
+
+--disable_warnings
+DROP VIEW IF EXISTS v1;
+DROP VIEW IF EXISTS v2;
+DROP FUNCTION IF EXISTS f1;
+DROP FUNCTION IF EXISTS f2;
+--enable_warnings
+
+--echo
+
+--echo #
+--echo # - Create required objects.
+--echo #
+
+--echo
+
+CREATE FUNCTION f1() RETURNS VARCHAR(65525) RETURN 'Hello';
+
+--echo
+
+CREATE FUNCTION f2() RETURNS TINYINT RETURN 1;
+
+--echo
+
+CREATE VIEW v1 AS SELECT f1();
+
+--echo
+
+CREATE VIEW v2 AS SELECT f2();
+
+--echo
+
+--echo #
+--echo # - Check.
+--echo #
+
+--echo
+
+SELECT DATA_TYPE FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'v1';
+
+--echo
+
+SELECT DATA_TYPE FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = 'v2';
+
+--echo
+
+--echo #
+--echo # - Cleanup.
+--echo #
+
+--echo
+
+DROP FUNCTION f1;
+DROP FUNCTION f2;
+DROP VIEW v1;
+DROP VIEW v2;
+
+--echo
+
+###########################################################################
+
+--echo End of 5.1 tests

sql/item_func.h

@@ -1535,6 +1535,11 @@ public:
   bool fix_fields(THD *thd, Item **ref);
   void fix_length_and_dec(void);
   bool is_expensive() { return 1; }
+
+  inline Field *get_sp_result_field()
+  {
+    return sp_result_field;
+  }
 };
 
 

sql/sql_select.cc

@@ -9301,6 +9301,36 @@ Field *create_tmp_field(THD *thd, TABLE *table,Item *item, Item::Type type,
   }
   /* Fall through */
   case Item::FUNC_ITEM:
+    if (((Item_func *) item)->functype() == Item_func::FUNC_SP)
+    {
+      Item_func_sp *item_func_sp= (Item_func_sp *) item;
+      Field *sp_result_field= item_func_sp->get_sp_result_field();
+
+      if (make_copy_field)
+      {
+        DBUG_ASSERT(item_func_sp->result_field);
+        *from_field= item_func_sp->result_field;
+      }
+      else
+      {
+        *((*copy_func)++)= item;
+      }
+
+      Field *result_field=
+        create_tmp_field_from_field(thd,
+                                    sp_result_field,
+                                    item_func_sp->name,
+                                    table,
+                                    NULL,
+                                    convert_blob_length);
+
+      if (modify_item)
+        item->set_result_field(result_field);
+
+      return result_field;
+    }
+
+    /* Fall through */
   case Item::COND_ITEM:
   case Item::FIELD_AVG_ITEM:
   case Item::FIELD_STD_ITEM: