diff options
Diffstat (limited to 'lib/sqlalchemy/orm/loading.py')
| -rw-r--r-- | lib/sqlalchemy/orm/loading.py | 54 |
1 files changed, 42 insertions, 12 deletions
diff --git a/lib/sqlalchemy/orm/loading.py b/lib/sqlalchemy/orm/loading.py index 54b96c215..7974d94c5 100644 --- a/lib/sqlalchemy/orm/loading.py +++ b/lib/sqlalchemy/orm/loading.py @@ -972,17 +972,17 @@ def _instance_processor( if not refresh_state and _polymorphic_from is not None: key = ("loader", path.path) + if key in context.attributes and context.attributes[key].strategy == ( ("selectinload_polymorphic", True), ): - selectin_load_via = mapper._should_selectin_load( - context.attributes[key].local_opts["entities"], - _polymorphic_from, - ) + option_entities = context.attributes[key].local_opts["entities"] else: - selectin_load_via = mapper._should_selectin_load( - None, _polymorphic_from - ) + option_entities = None + selectin_load_via = mapper._should_selectin_load( + option_entities, + _polymorphic_from, + ) if selectin_load_via and selectin_load_via is not _polymorphic_from: # only_load_props goes w/ refresh_state only, and in a refresh @@ -990,8 +990,13 @@ def _instance_processor( # loading does not apply assert only_load_props is None - callable_ = _load_subclass_via_in(context, path, selectin_load_via) - + callable_ = _load_subclass_via_in( + context, + path, + selectin_load_via, + _polymorphic_from, + option_entities, + ) PostLoad.callable_for_path( context, load_path, @@ -1212,17 +1217,42 @@ def _instance_processor( return _instance -def _load_subclass_via_in(context, path, entity): +def _load_subclass_via_in( + context, path, entity, polymorphic_from, option_entities +): mapper = entity.mapper + # TODO: polymorphic_from seems to be a Mapper in all cases. + # this is likely not needed, but as we dont have typing in loading.py + # yet, err on the safe side + polymorphic_from_mapper = polymorphic_from.mapper + not_against_basemost = polymorphic_from_mapper.inherits is not None + zero_idx = len(mapper.base_mapper.primary_key) == 1 - if entity.is_aliased_class: - q, enable_opt, disable_opt = mapper._subclass_load_via_in(entity) + if entity.is_aliased_class or not_against_basemost: + q, enable_opt, disable_opt = mapper._subclass_load_via_in( + entity, polymorphic_from + ) else: q, enable_opt, disable_opt = mapper._subclass_load_via_in_mapper def do_load(context, path, states, load_only, effective_entity): + if not option_entities: + # filter out states for those that would have selectinloaded + # from another loader + # TODO: we are currently ignoring the case where the + # "selectin_polymorphic" option is used, as this is much more + # complex / specific / very uncommon API use + states = [ + (s, v) + for s, v in states + if s.mapper._would_selectin_load_only_from_given_mapper(mapper) + ] + + if not states: + return + orig_query = context.query options = (enable_opt,) + orig_query._with_options + (disable_opt,) |