Comment 2 for bug 1545577

Reviewed: https://review.openstack.org/285425
Committed: https://git.openstack.org/cgit/openstack/heat/commit/?id=3f23ffb59224a3a923de052d924f680354222c00
Submitter: Jenkins
Branch: master

commit 3f23ffb59224a3a923de052d924f680354222c00
Author: Rabi Mishra <email address hidden>
Date: Fri Feb 26 20:12:15 2016 +0530

    Use transactions instead of session.flush

    Currently we do session.flush() after deleting objects. It
    would be better to use explicit transactions.

    This also changes update_and_save and delete to use
    'subtransaction=True' as they may part of an already ongoing
    transaction(ex. stack soft_delete in stack_delete), and the
    flush operation takes place within that transaction.

    Change-Id: I8fba68eda63e0e64e8b5e55eab92cf6a8ac5a503
    Closes-Bug: #1545577