diff options
Diffstat (limited to 'django/db/models/sql')
| -rw-r--r-- | django/db/models/sql/query.py | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py index 3044882a86..e6a3cd2679 100644 --- a/django/db/models/sql/query.py +++ b/django/db/models/sql/query.py @@ -679,12 +679,16 @@ class Query(object): for the join to contain NULL values on the left. If 'unconditional' is False, the join is only promoted if it is nullable, otherwise it is always promoted. + + Returns True if the join was promoted. """ if ((unconditional or self.alias_map[alias][NULLABLE]) and self.alias_map[alias] != self.LOUTER): data = list(self.alias_map[alias]) data[JOIN_TYPE] = self.LOUTER self.alias_map[alias] = tuple(data) + return True + return False def change_aliases(self, change_map): """ @@ -1294,10 +1298,12 @@ class Query(object): final_alias = join[LHS_ALIAS] col = join[LHS_JOIN_COL] joins = joins[:-1] + promote = False for join in joins[1:]: # Only nullable aliases are promoted, so we don't end up # doing unnecessary left outer joins here. - self.promote_alias(join) + if self.promote_alias(join, promote): + promote = True self.select.append((final_alias, col)) self.select_fields.append(field) except MultiJoin: |