diff options
Diffstat (limited to 'lib/sqlalchemy/orm/query.py')
| -rw-r--r-- | lib/sqlalchemy/orm/query.py | 70 |
1 files changed, 30 insertions, 40 deletions
diff --git a/lib/sqlalchemy/orm/query.py b/lib/sqlalchemy/orm/query.py index 1fc299cec..5588828eb 100644 --- a/lib/sqlalchemy/orm/query.py +++ b/lib/sqlalchemy/orm/query.py @@ -728,15 +728,6 @@ class Query(Generative): """ self._enable_eagerloads = value - def _no_yield_per(self, message): - raise sa_exc.InvalidRequestError( - "The yield_per Query option is currently not " - "compatible with %s eager loading. Please " - "specify lazyload('*') or query.enable_eagerloads(False) in " - "order to " - "proceed with query.yield_per()." % message - ) - @_generative def with_labels(self): """Apply column labels to the return value of Query.statement. @@ -3238,7 +3229,7 @@ class Query(Generative): :ref:`faq_query_deduplicating` """ - return list(self) + return self._iter().all() @_generative @_assertions(_no_clauseelement_condition) @@ -3283,14 +3274,11 @@ class Query(Generative): :meth:`_query.Query.one_or_none` """ + # replicates limit(1) behavior if self._statement is not None: - ret = list(self)[0:1] + return self._iter().first() else: - ret = list(self[0:1]) - if len(ret) > 0: - return ret[0] - else: - return None + return self.limit(1)._iter().first() def one_or_none(self): """Return at most one result or raise an exception. @@ -3316,17 +3304,7 @@ class Query(Generative): :meth:`_query.Query.one` """ - ret = list(self) - - l = len(ret) - if l == 1: - return ret[0] - elif l == 0: - return None - else: - raise orm_exc.MultipleResultsFound( - "Multiple rows were found for one_or_none()" - ) + return self._iter().one_or_none() def one(self): """Return exactly one result or raise an exception. @@ -3346,19 +3324,7 @@ class Query(Generative): :meth:`_query.Query.one_or_none` """ - try: - ret = self.one_or_none() - except orm_exc.MultipleResultsFound as err: - util.raise_( - orm_exc.MultipleResultsFound( - "Multiple rows were found for one()" - ), - replace_context=err, - ) - else: - if ret is None: - raise orm_exc.NoResultFound("No row was found for one()") - return ret + return self._iter().one() def scalar(self): """Return the first element of the first result or None @@ -3379,6 +3345,7 @@ class Query(Generative): This results in an execution of the underlying query. """ + # TODO: not sure why we can't use result.scalar() here try: ret = self.one() if not isinstance(ret, collections_abc.Sequence): @@ -3388,6 +3355,24 @@ class Query(Generative): return None def __iter__(self): + return self._iter().__iter__() + + # TODO: having _iter(), _execute_and_instances, _connection_from_session, + # etc., is all too much. + + # new recipes / extensions should be based on an event hook of some kind, + # can allow an execution that would return a Result to take in all the + # information and return a different Result. this has to be at + # the session / connection .execute() level, and can perhaps be + # before_execute() but needs to be focused around rewriting of results. + + # the dialect do_execute() *may* be this but that seems a bit too low + # level. it may need to be ORM session based and be a session event, + # becasue it might not invoke the cursor, might invoke for multiple + # connections, etc. OK really has to be a session level event in this + # case to support horizontal sharding. + + def _iter(self): context = self._compile_context() context.statement.label_style = LABEL_STYLE_TABLENAME_PLUS_COL if self._autoflush: @@ -4795,6 +4780,9 @@ class QueryContext(object): "post_load_paths", "identity_token", "single_inh_entities", + "is_single_entity", + "loaders_require_uniquing", + "loaders_require_buffering", ) def __init__(self, query): @@ -4815,6 +4803,8 @@ class QueryContext(object): self.whereclause = query._criterion self.order_by = query._order_by + self.is_single_entity = query.is_single_entity + self.loaders_require_buffering = self.loaders_require_uniquing = False self.multi_row_eager_loaders = False self.adapter = None self.froms = () |