Comment 4 for bug 1777892

Reviewed: https://review.opendev.org/657187
Committed: https://git.openstack.org/cgit/openstack/keystone/commit/?id=f43954be9419e96fbe9d231aa1f5ae32cd0142eb
Submitter: Zuul
Branch: master

commit f43954be9419e96fbe9d231aa1f5ae32cd0142eb
Author: wangxiyuan <email address hidden>
Date: Sun May 5 10:39:17 2019 +0800

    Drop limit columns

    The service_id, region_id and resource_name columns in limit table
    is useless now. These info can be got by 'registered_limit_id'
    column from registered limit table. So there is no data migration
    needed.

    Since this is a silent change for end users, there is no need for
    a release note as well.

    Related-Bug: #1777892
    Change-Id: Ibf4aa81dad7c5ebbd5599a55237cc5a658223432