diff options
Diffstat (limited to 'lib/sqlalchemy/orm/query.py')
| -rw-r--r-- | lib/sqlalchemy/orm/query.py | 21 |
1 files changed, 17 insertions, 4 deletions
diff --git a/lib/sqlalchemy/orm/query.py b/lib/sqlalchemy/orm/query.py index 34daa707f..2b1a88582 100644 --- a/lib/sqlalchemy/orm/query.py +++ b/lib/sqlalchemy/orm/query.py @@ -1388,6 +1388,12 @@ class Query(object): * ``'read'`` - translates to ``LOCK IN SHARE MODE`` (for MySQL), and ``FOR SHARE`` (for PostgreSQL) + * ``'no_key'`` - translates to ``FOR NO KEY UPDATE`` (for PostgreSQL), + and ``FOR UPDATE`` on other backends + + * ``'no_key_nowait'`` - translates to ``FOR NO KEY UPDATE NOWAIT`` (for PostgreSQL), + and ``FOR UPDATE`` on other backends + .. seealso:: :meth:`.Query.with_for_update` - improved API for @@ -1397,7 +1403,7 @@ class Query(object): self._for_update_arg = LockmodeArg.parse_legacy_query(mode) @_generative() - def with_for_update(self, read=False, nowait=False, of=None): + def with_for_update(self, read=False, nowait=False, of=None, no_key=None): """return a new :class:`.Query` with the specified options for the ``FOR UPDATE`` clause. @@ -1411,10 +1417,12 @@ class Query(object): E.g.:: q = sess.query(User).with_for_update(nowait=True, of=User) + q = sess.query(User).with_for_update(nowait=True, no_key=True) - The above query on a Postgresql backend will render like:: + The above queries on a Postgresql backend will render like, accordingly:: SELECT users.id AS users_id FROM users FOR UPDATE OF users NOWAIT + SELECT users.id AS users_id FROM users FOR NO KEY UPDATE NOWAIT .. versionadded:: 0.9.0 :meth:`.Query.with_for_update` supersedes the :meth:`.Query.with_lockmode` method. @@ -1425,7 +1433,7 @@ class Query(object): full argument and behavioral description. """ - self._for_update_arg = LockmodeArg(read=read, nowait=nowait, of=of) + self._for_update_arg = LockmodeArg(read=read, nowait=nowait, of=of, no_key=no_key) @_generative() def params(self, *args, **kwargs): @@ -3411,6 +3419,7 @@ class LockmodeArg(ForUpdateArg): if mode in (None, False): return None + no_key = nowait = read = False if mode == "read": read = True nowait = False @@ -3419,11 +3428,15 @@ class LockmodeArg(ForUpdateArg): elif mode == "update_nowait": nowait = True read = False + elif mode == "no_key": + no_key = True + elif mode == "no_key_nowait": + no_key = nowait = True else: raise sa_exc.ArgumentError( "Unknown with_lockmode argument: %r" % mode) - return LockmodeArg(read=read, nowait=nowait) + return LockmodeArg(read=read, nowait=nowait, no_key=no_key) class _QueryEntity(object): |