Added a test for the SELECT DISTINCT ON postgresqlism.

Test currently fails due to two problems in postgres.py, but I'm leaving
it uncorrected for now as its not clear what the original intent was
for lists.

diff --git a/test/dialect/postgres.py b/test/dialect/postgres.py
index 221f7660a9f990861f8bccbbea3513c2fb25f9ad..c12115c9aea7b612b3d24dfad41be497b7c075ea 100644 (file)
--- a/test/dialect/postgres.py
+++ b/test/dialect/postgres.py
@@ -114,6 +114,24 @@ class MiscTest(AssertMixin):
         finally:
             t.drop(checkfirst=True)
 
+    @testing.supported('postgres')
+    def test_distinct_on(self):
+        t = Table('mytable', MetaData(testbase.db),
+                  Column('id', Integer, primary_key=True),
+                  Column('a', String(8)))
+        self.assertEquals(
+            str(t.select(distinct=t.c.a)),
+            'SELECT DISTINCT ON (mytable.a) mytable.id, mytable.a \n'
+            'FROM mytable')
+        self.assertEquals(
+            str(t.select(distinct=['id','a'])),
+            'SELECT DISTINCT ON (id, a) mytable.id, mytable.a \n'
+            'FROM mytable')
+        self.assertEquals(
+            str(t.select(distinct=[t.c.id, t.c.a])),
+            'SELECT DISTINCT ON (mytable.id, mytable.a) mytable.id, mytable.a \n'
+            'FROM mytable')
+
     @testing.supported('postgres')
     def test_schema_reflection(self):
         """note: this test requires that the 'alt_schema' schema be separate and accessible by the test user"""