Function needed compare_type so that its type is set as the type in boolean expressions

1 files changed, 3 insertions, 1 deletions

diff --git a/lib/sqlalchemy/sql.py b/lib/sqlalchemy/sql.py
index 2a1686e12..cbd9a82f3 100644
--- a/lib/sqlalchemy/sql.py
+++ b/lib/sqlalchemy/sql.py
@@ -796,7 +796,9 @@ class Function(ClauseList, ColumnElement):
         return select([self])
     def hash_key(self):
         return self.name + "(" + string.join([c.hash_key() for c in self.clauses], ", ") + ")"
-            
+    def _compare_type(self, obj):
+        return self.type
+                
 class BinaryClause(ClauseElement):
     """represents two clauses with an operator in between"""
     def __init__(self, left, right, operator, type=None):