From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Thu, 21 Jun 2007 17:42:42 +0000 (+0000)
Subject: - added standalone distinct() function in addition to column.distinct()
X-Git-Tag: rel_0_3_9~70
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3c1a7710f0c1278a18ddeec28f3f67362fbc5ae7;p=thirdparty%2Fsqlalchemy%2Fsqlalchemy.git

- added standalone distinct() function in addition to column.distinct()
[ticket:558]
---

diff --git a/CHANGES b/CHANGES
index 5e3f960d01..5bf80221a3 100644
--- a/CHANGES
+++ b/CHANGES
@@ -25,6 +25,8 @@
       to polymorphic mappers that are using a straight "outerjoin"
       clause
 - sql
+    - added standalone distinct() function in addition to column.distinct()
+      [ticket:558]
     - result.last_inserted_ids() should return a list that is identically
       sized to the primary key constraint of the table.  values that were 
       "passively" created and not available via cursor.lastrowid will be None.
diff --git a/lib/sqlalchemy/sql.py b/lib/sqlalchemy/sql.py
index f9ac753fa8..92b51dd258 100644
--- a/lib/sqlalchemy/sql.py
+++ b/lib/sqlalchemy/sql.py
@@ -34,7 +34,7 @@ __all__ = ['AbstractDialect', 'Alias', 'ClauseElement', 'ClauseParameters',
            'Compiled', 'CompoundSelect', 'Executor', 'FromClause', 'Join',
            'Select', 'Selectable', 'TableClause', 'alias', 'and_', 'asc',
            'between_', 'bindparam', 'case', 'cast', 'column', 'delete',
-           'desc', 'except_', 'except_all', 'exists', 'extract', 'func', 'modifier',
+           'desc', 'distinct', 'except_', 'except_all', 'exists', 'extract', 'func', 'modifier',
            'insert', 'intersect', 'intersect_all', 'join', 'literal',
            'literal_column', 'not_', 'null', 'or_', 'outerjoin', 'select',
            'subquery', 'table', 'text', 'union', 'union_all', 'update',]
@@ -375,6 +375,11 @@ def not_(clause):
 
     return clause._negate()
 
+def distinct(expr):
+    """return a ``DISTINCT`` clause."""
+    
+    return _UnaryExpression(expr, operator="DISTINCT")
+
 def between(ctest, cleft, cright):
     """Return a ``BETWEEN`` predicate clause.
 
@@ -749,8 +754,11 @@ class _FunctionGenerator(object):
         return _Function(self.__names[-1], packagenames=self.__names[0:-1], *c, **o)
 
 func = _FunctionGenerator()
+
+# TODO: use UnaryExpression for this instead ?
 modifier = _FunctionGenerator(group=False)
 
+    
 def _compound_select(keyword, *selects, **kwargs):
     return CompoundSelect(keyword, *selects, **kwargs)
 
diff --git a/test/sql/select.py b/test/sql/select.py
index 2f627ee8fe..d8b872098a 100644
--- a/test/sql/select.py
+++ b/test/sql/select.py
@@ -244,6 +244,15 @@ sq.myothertable_othername AS sq_myothertable_othername FROM (" + sqstring + ") A
             checkparams = {'myothertable_othername': 'asdf', 'myothertable_othername_1':'foo', 'myothertable_otherid': 9, 'mytable_myid': 12}
         )
 
+    def testdistinct(self):
+        self.runtest(
+            select([table1.c.myid.distinct()]), "SELECT DISTINCT mytable.myid FROM mytable"
+        )
+
+        self.runtest(
+            select([distinct(table1.c.myid)]), "SELECT DISTINCT mytable.myid FROM mytable"
+        )
+        
     def testoperators(self):
         self.runtest(
             table1.select((table1.c.myid != 12) & ~(table1.c.name=='john')),