Commit 1006d6eb authored by Malcolm Tredinnick's avatar Malcolm Tredinnick
Browse files

Fixed #1530 -- make count() respect distinct() on QuerySets. Create some 

tests for this as well. Thanks to Adam Endicott for the original patch on which
this is based.



git-svn-id: http://code.djangoproject.com/svn/django/trunk@2902 bcc190cf-cafb-0310-a4f2-bffc1f526a37
parent aa11b3ea

django/db/models/query.py

+6 −1
Original line number Diff line number Diff line
@@ -182,6 +182,11 @@ class QuerySet(object): 
        counter._select_related = False

        select, sql, params = counter._get_sql_clause()

        cursor = connection.cursor()

        if self._distinct:

            id_col = "%s.%s" % (backend.quote_name(self.model._meta.db_table),

                    backend.quote_name(self.model._meta.pk.column))

            cursor.execute("SELECT COUNT(DISTINCT(%s))" % id_col + sql, params)

        else:

            cursor.execute("SELECT COUNT(*)" + sql, params)

        return cursor.fetchone()[0]

tests/modeltests/many_to_many/models.py

+7 −0
Original line number Diff line number Diff line
@@ -82,6 +82,13 @@ API_TESTS = """ 
>>> Article.objects.filter(publications__title__startswith="Science").distinct()

[NASA uses Python]



# The count() function respects distinct() as well.

>>> Article.objects.filter(publications__title__startswith="Science").count()

2



>>> Article.objects.filter(publications__title__startswith="Science").distinct().count()

1



# Reverse m2m queries are supported (i.e., starting at the table that doesn't

# have a ManyToManyField).

>>> Publication.objects.filter(id__exact=1)

tests/modeltests/many_to_one/models.py

+6 −0
Original line number Diff line number Diff line
@@ -205,6 +205,12 @@ John Smith 
>>> Reporter.objects.filter(article__headline__startswith='This').distinct()

[John Smith]



# Counting in the opposite direction works in conjunction with distinct()

>>> Reporter.objects.filter(article__headline__startswith='This').count()

3

>>> Reporter.objects.filter(article__headline__startswith='This').distinct().count()

1



# Queries can go round in circles.

>>> Reporter.objects.filter(article__reporter__first_name__startswith='John')

[John Smith, John Smith, John Smith, John Smith]