sql clear_expired_metering_data breaks resource metadata

[ZhiQiang Fan]

no matter what ttl is, the code:

https://github.com/openstack/ceilometer/blob/926f781096dcfa77a8f63e403c0959de20e182aa/ceilometer/storage/impl_sqlalchemy.py#L362

            for table in [models.MetaText, models.MetaBigInt,
                          models.MetaFloat, models.MetaBool]:
                (session.query(table)
                 .join(sample_subq, sample_subq.c.id == table.id)
                 .delete())

will clean all the data in the four tables, then metadata query for resource api will no longer works

sample id is primary index generated by sql, metada id is resource internal_id, compare them is non sense

we should clean metadata for those cleaned resource, not samples

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/153902

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/153902
Committed: https://git.openstack.org/cgit/openstack/ceilometer/commit/?id=5a65b4de0fe46967e76832c2acf4924a53b18612
Submitter: Jenkins
Branch: master

commit 5a65b4de0fe46967e76832c2acf4924a53b18612
Author: ZhiQiang Fan <email address hidden>
Date: Sat Feb 7 16:23:20 2015 +0800

    metering data ttl sql backend breaks resource metadata

    The implementation for sql clear_expired_metering_data() uses delete()
    on join() for four metatada tables, which will cause clear whole
    tables no matter what join returns. And it associates metadata id
    with sample id which makes no sense, the metadata id is resource's
    internal id.

    Change-Id: I98219bf27a0a765838d45386b7ae6b6b980b1ae9
    Closes-Bug: #1419239

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/juno
Review: https://review.openstack.org/154530

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/154530
Committed: https://git.openstack.org/cgit/openstack/ceilometer/commit/?id=989fac5c5821739fef4809b0d75840e3bc4685bf
Submitter: Jenkins
Branch: stable/juno

commit 989fac5c5821739fef4809b0d75840e3bc4685bf
Author: ZhiQiang Fan <email address hidden>
Date: Sat Feb 7 16:23:20 2015 +0800

    metering data ttl sql backend breaks resource metadata

    The implementation for sql clear_expired_metering_data() uses delete()
    on join() for four metatada tables, which will cause clear whole
    tables no matter what join returns. And it associates metadata id
    with sample id which makes no sense, the metadata id is resource's
    internal id.

    Change-Id: I98219bf27a0a765838d45386b7ae6b6b980b1ae9
    Closes-Bug: #1419239
    (cherry picked from commit 5a65b4de0fe46967e76832c2acf4924a53b18612)