diff options
Diffstat (limited to 'django/db/models/sql/query.py')
| -rw-r--r-- | django/db/models/sql/query.py | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/django/db/models/sql/query.py b/django/db/models/sql/query.py index f15e4ac2f2..73584a65fa 100644 --- a/django/db/models/sql/query.py +++ b/django/db/models/sql/query.py @@ -716,7 +716,6 @@ class Query(object): alias = table_name self.table_map[alias] = [alias] self.alias_refcount[alias] = 1 - #self.alias_map[alias] = None self.tables.append(alias) return alias, True @@ -1188,6 +1187,8 @@ class Query(object): subtree = False connector = AND for child in q_object.children: + if connector == OR: + refcounts_before = self.alias_refcount.copy() if isinstance(child, Node): self.where.start_subtree(connector) self.add_q(child, used_aliases) @@ -1195,6 +1196,27 @@ class Query(object): else: self.add_filter(child, connector, q_object.negated, can_reuse=used_aliases) + if connector == OR: + # Aliases that were newly added or not used at all need to + # be promoted to outer joins if they are nullable relations. + # (they shouldn't turn the whole conditional into the empty + # set just because they don't match anything). + # FIXME: There's some (a lot of!) overlap with the similar + # OR promotion in add_filter(). It's not quite identical, + # but is very similar. So pulling out the common bits is + # something for later (code smell: too much indentation + # here) + considered = {} + for alias in self.tables: + if alias not in used_aliases: + continue + if (alias not in refcounts_before or + self.alias_refcount[alias] == + refcounts_before[alias]): + parent = self.alias_map[alias][LHS_ALIAS] + must_promote = considered.get(parent, False) + promoted = self.promote_alias(alias, must_promote) + considered[alias] = must_promote or promoted connector = q_object.connector if q_object.negated: self.where.negate() |