Bug#50918: Date columns treated differently in Views than in

Base Tables

The type inferrence of a view column caused the result to be
interpreted as the wrong type: DATE colums were interpreted
as TIME and TIME as DATETIME. This happened because view
columns are represented by Item_ref objects as opposed to
Item_field's. Item_ref had no method for retrieving a TIME
value and thus was forced to depend on the default
implementation for any expression, which caused the
expression to be evaluated as a string and then parsed into
a TIME/DATETIME value.

Fixed by letting Item_ref classes forward the request for a
TIME value to the referred Item - which is a field in this
case - this reads the TIME value directly without
conversion.

mysql-test/r/type_date.result

@@ -275,4 +275,25 @@ select * from t1 where a between '0000-00-01' and '0000-00-02';
 a
 0000-00-01
 drop table t1;
+#
+# Bug#50918: Date columns treated differently in Views than in Base
+# Tables
+#
+CREATE TABLE t1 ( the_date DATE, the_time TIME );
+INSERT INTO t1 VALUES ( '2010-01-01', '01:01:01' );
+SELECT * FROM t1 t11 JOIN t1 t12 ON addtime( t11.the_date, t11.the_time ) = 
+addtime( t12.the_date, t12.the_time );
+the_date	the_time	the_date	the_time
+2010-01-01	01:01:01	2010-01-01	01:01:01
+CREATE VIEW v1 AS SELECT * FROM t1;
+SELECT * FROM t1 JOIN v1 ON addtime( t1.the_date, t1.the_time ) = 
+addtime( v1.the_date, v1.the_time );
+the_date	the_time	the_date	the_time
+2010-01-01	01:01:01	2010-01-01	01:01:01
+SELECT * FROM t1 JOIN v1 ON addtime( t1.the_date, t1.the_time ) = 
+addtime( cast(v1.the_date AS DATETIME), v1.the_time );
+the_date	the_time	the_date	the_time
+2010-01-01	01:01:01	2010-01-01	01:01:01
+DROP TABLE t1;
+DROP VIEW v1;
 End of 5.1 tests

mysql-test/t/type_date.test

@@ -246,4 +246,24 @@ insert into t1 values ('0000-01-01'), ('0000-00-01'), ('0001-01-01');
 select * from t1 where a between '0000-00-01' and '0000-00-02';
 drop table t1;
 
+--echo #
+--echo # Bug#50918: Date columns treated differently in Views than in Base
+--echo # Tables
+--echo #
+CREATE TABLE t1 ( the_date DATE, the_time TIME );
+INSERT INTO t1 VALUES ( '2010-01-01', '01:01:01' );
+
+SELECT * FROM t1 t11 JOIN t1 t12 ON addtime( t11.the_date, t11.the_time ) = 
+                                    addtime( t12.the_date, t12.the_time );
+
+CREATE VIEW v1 AS SELECT * FROM t1;
+SELECT * FROM t1 JOIN v1 ON addtime( t1.the_date, t1.the_time ) = 
+                            addtime( v1.the_date, v1.the_time );
+
+SELECT * FROM t1 JOIN v1 ON addtime( t1.the_date, t1.the_time ) = 
+                            addtime( cast(v1.the_date AS DATETIME), v1.the_time );
+
+DROP TABLE t1;
+DROP VIEW v1;
+
 --echo End of 5.1 tests

sql/item.h

@@ -2320,6 +2320,11 @@ public:
     if (ref && result_type() == ROW_RESULT)
       (*ref)->bring_value();
   }
+  bool get_time(MYSQL_TIME *ltime)
+  {
+    DBUG_ASSERT(fixed);
+    return (*ref)->get_time(ltime);
+  }
 
 };