diff options
Diffstat (limited to 'lib/sqlalchemy/orm')
| -rw-r--r-- | lib/sqlalchemy/orm/query.py | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/lib/sqlalchemy/orm/query.py b/lib/sqlalchemy/orm/query.py index b22a10b55..0ce84435f 100644 --- a/lib/sqlalchemy/orm/query.py +++ b/lib/sqlalchemy/orm/query.py @@ -1250,7 +1250,7 @@ class Query(object): (left, right)) left_mapper, left_selectable, left_is_aliased = _entity_info(left) - right_mapper, right_selectable, is_aliased_class = _entity_info(right) + right_mapper, right_selectable, right_is_aliased = _entity_info(right) if right_mapper and prop and \ not right_mapper.common_parent(prop.mapper): @@ -1279,7 +1279,7 @@ class Query(object): need_adapter = True aliased_entity = right_mapper and \ - not is_aliased_class and \ + not right_is_aliased and \ ( right_mapper.with_polymorphic or isinstance( @@ -1342,8 +1342,16 @@ class Query(object): ) ) - join_to_left = not is_aliased_class and not left_is_aliased - + # this is an overly broad assumption here, but there's a + # very wide variety of situations where we rely upon orm.join's + # adaption to glue clauses together, with joined-table inheritance's + # wide array of variables taking up most of the space. + # Setting the flag here is still a guess, so it is a bug + # that we don't have definitive criterion to determine when + # adaption should be enabled (or perhaps that we're even doing the + # whole thing the way we are here). + join_to_left = not right_is_aliased and not left_is_aliased + if self._from_obj and left_selectable is not None: replace_clause_index, clause = sql_util.find_join_source( self._from_obj, @@ -1351,10 +1359,16 @@ class Query(object): if clause is not None: # the entire query's FROM clause is an alias of itself (i.e. # from_self(), similar). if the left clause is that one, - # ensure it aliases to the left side. + # ensure it adapts to the left side. if self._from_obj_alias and clause is self._from_obj[0]: join_to_left = True - + + # An exception case where adaption to the left edge is not + # desirable. See above note on join_to_left. + if join_to_left and isinstance(clause, expression.Join) and \ + sql_util.clause_is_present(left_selectable, clause): + join_to_left = False + clause = orm_join(clause, right, onclause, isouter=outerjoin, |