Ticket #9797: annotate-count.2.diff

django/db/models/sql/aggregates.py

@@ -27 +27 @@
     def relabel_aliases(self, change_map):
         if self.col_alias in change_map:
             self.col_alias = change_map[self.col_alias]
+        if isinstance(self.lookup, (list, tuple)):
+            self.lookup = (change_map.get(self.lookup[0], self.lookup[0]), self.lookup[1])
 
     def field_name(self, quote_func):
         if not quote_func:
             quote_func = lambda x: x
         if hasattr(self, 'col_alias'):
             return '.'.join([quote_func(self.col_alias), quote_func(self.field.column)])
+        elif isinstance(self.lookup, (list, tuple)):
+            return ('%s.%s' % tuple([quote_func(c) for c in self.lookup]))
+        elif hasattr(self.lookup, 'as_sql'):
+            return self.lookup.as_sql(quote_func)
         else:
             return self.lookup
 
@@ -69 +75 @@
 
     def __init__(self, lookup, distinct=False):
         super(Count, self).__init__('COUNT', lookup, distinct=distinct and 'DISTINCT ' or '')
+

django/db/models/sql/query.py

@@ -274 +274 @@
         """
         Performs a COUNT() query using the current filter constraints.
         """
-        from subqueries import CountQuery
+        from django.db.models import Count as AggCount
+        from django.db.models.sql.aggregates import Count as AggCount2
         obj = self.clone()
-        obj.clear_ordering(True)
         obj.clear_limits()
+        obj.clear_ordering(True)
         obj.select_related = False
         obj.related_select_cols = []
         obj.related_select_fields = []
-        if len(obj.select) > 1:
-            obj = self.clone(CountQuery, _query=obj, where=self.where_class(),
-                    distinct=False)
-            obj.select = []
-            obj.aggregate_select = {}
-            obj.extra_select = {}
-        obj.add_count_column()
-        data = obj.execute_sql(SINGLE)
-        if not data:
-            return 0
-        number = data[0]
 
+        if not obj.distinct:
+            if not obj.select:
+                obj.aggregate_select['f'] = AggCount2('*', distinct=obj.distinct)
+            else:
+                obj.aggregate_select['f'] = AggCount2(obj.select[0], distinct=obj.distinct)
+        else:
+            if not obj.select:
+                obj.add_aggregate(AggCount('pk', distinct=obj.distinct), obj.model, 'f', True)
+            else:
+                agg = AggCount2(obj.select[0], distinct=obj.distinct)
+                agg.reduce = True
+                obj.aggregate_select['f'] = agg
+        number = obj.get_aggregation()['f']
+        
         # Apply offset and limit constraints manually, since using LIMIT/OFFSET
         # in SQL (in variants that provide them) doesn't change the COUNT
         # output.

tests/regressiontests/aggregation_regress/models.py

@@ -121 +121 @@
 ...
 FieldError: Cannot resolve keyword 'foo' into field. Choices are: authors, id, isbn, name, pages, price, publisher, store, num_authors
 
+>>> Book.objects.annotate(num_authors=Count('authors')).count()
+6
 """
 }