Django

Code

Changeset 4232

Show
Ignore:
Timestamp:
12/20/06 07:57:17 (2 years ago)
Author:
russellm
Message:

Fixed problem with assiging an empty list to m2m related descriptors, introduced in [4231].

Files:

Legend:

Unmodified
Added
Removed
Modified
Copied
Moved

  • django/trunk/django/db/models/fields/related.py

    r4231 r4232  
    318318            from django.db import connection 
    319319 
    320             # Add the newly created or already existing objects to the join table. 
    321             # First find out which items are already added, to avoid adding them twice 
    322             new_ids = set([obj._get_pk_val() for obj in objs]) 
    323             cursor = connection.cursor() 
    324             cursor.execute("SELECT %s FROM %s WHERE %s = %%s AND %s IN (%s)" % \ 
    325                 (target_col_name, self.join_table, source_col_name, 
    326                 target_col_name, ",".join(['%s'] * len(new_ids))), 
    327                 [self._pk_val] + list(new_ids)) 
    328             if cursor.rowcount is not None and cursor.rowcount != 0: 
    329                 existing_ids = set([row[0] for row in cursor.fetchmany(cursor.rowcount)]) 
    330             else: 
    331                 existing_ids = set() 
    332  
    333             # Add the ones that aren't there already 
    334             for obj_id in (new_ids - existing_ids): 
    335                 cursor.execute("INSERT INTO %s (%s, %s) VALUES (%%s, %%s)" % \ 
    336                     (self.join_table, source_col_name, target_col_name), 
    337                     [self._pk_val, obj_id]) 
    338             transaction.commit_unless_managed() 
     320            # If there aren't any objects, there is nothing to do. 
     321            if objs: 
     322                # Add the newly created or already existing objects to the join table. 
     323                # First find out which items are already added, to avoid adding them twice 
     324                new_ids = set([obj._get_pk_val() for obj in objs]) 
     325                cursor = connection.cursor() 
     326                cursor.execute("SELECT %s FROM %s WHERE %s = %%s AND %s IN (%s)" % \ 
     327                    (target_col_name, self.join_table, source_col_name, 
     328                    target_col_name, ",".join(['%s'] * len(new_ids))), 
     329                    [self._pk_val] + list(new_ids)) 
     330                if cursor.rowcount is not None and cursor.rowcount != 0: 
     331                    existing_ids = set([row[0] for row in cursor.fetchmany(cursor.rowcount)]) 
     332                else: 
     333                    existing_ids = set() 
     334 
     335                # Add the ones that aren't there already 
     336                for obj_id in (new_ids - existing_ids): 
     337                    cursor.execute("INSERT INTO %s (%s, %s) VALUES (%%s, %%s)" % \ 
     338                        (self.join_table, source_col_name, target_col_name), 
     339                        [self._pk_val, obj_id]) 
     340                transaction.commit_unless_managed() 
    339341 
    340342        def _remove_items(self, source_col_name, target_col_name, *objs): 

  • django/trunk/tests/modeltests/many_to_many/models.py

    r3661 r4232  
    232232[<Article: NASA uses Python>] 
    233233 
     234# An alternate to calling clear() is to assign the empty set 
     235>>> p1.article_set = [] 
     236>>> p1.article_set.all() 
     237[] 
     238 
     239>>> a2.publications = [p1, new_publication] 
     240>>> a2.publications.all() 
     241[<Publication: Highlights for Children>, <Publication: The Python Journal>] 
     242>>> a2.publications = [] 
     243>>> a2.publications.all() 
     244[] 
     245 
    234246"""}