diff options
| -rw-r--r-- | doc/build/session.rst | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/doc/build/session.rst b/doc/build/session.rst index da858a2ef..cbd33357b 100644 --- a/doc/build/session.rst +++ b/doc/build/session.rst @@ -249,6 +249,17 @@ The solution is to use proper cascading:: del user.addresses[1] session.flush() +Deleting based on Filter Criterion +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The caveat with ``Session.delete()`` is that you need to have an object handy already in order to delete. The Query includes a ``delete()`` method which deletes based on filtering criteria:: + + session.query(User).filter(User.id==7).delete() + +The ``Query.delete()`` method includes functionality to "expire" objects already in the session which +match the criteria. However it does have some caveats, including that "delete" and "delete-orphan" +cascades won't be fully expressed for collections which are already loaded. See the API docs for :meth:`~sqlalchemy.orm.query.Query.delete` for more details. + Flushing -------- |