[DB2 nosql] Ceilometer sample-list alway return nothing with two timestamp condition queries

[Lan Qi song]

1. I tried the following sample-list command:

[root@Controller ~]# ceilometer sample-list -m cpu_util
+--------------------------------------+----------+-------+---------------+------+---------------------+
| Resource ID | Name | Type | Volume | Unit | Timestamp |
+--------------------------------------+----------+-------+---------------+------+---------------------+
| a5074a11-d85e-4170-a042-466dd5d76d9c | cpu_util | gauge | 8.97666666667 | % | 2015-01-16T03:00:16 |
+--------------------------------------+----------+-------+---------------+------+---------------------+

Please notice that the timestamp value is "2015-01-16T03:00:16"

2. Next, I tried the second command :

[root@Controller ~]# ceilometer sample-list -m cpu_util -q 'timestamp>2015-01-16T03:00:15;timestamp<2015-01-16T03:00:17'
+-------------+------+------+--------+------+-----------+
| Resource ID | Name | Type | Volume | Unit | Timestamp |
+-------------+------+------+--------+------+-----------+
+-------------+------+------+--------+------+-----------+

It returned nothing, but the timestamp is between two timestamp conditions.

The reason for this problem is that

1. There is a concept named "datatype" of index in DB2 nosql, the default value is "varchar".
2. It will create an index for "timestamp" filed when using 'ceilometer-dbsync' command, but the 'datatype' is set to "varchar".
3. We should create an index for "timestamp" filed with a "datatype" set to "TIMESTAMP"

nosql>db.meter.getIndexes()
[{"v":0,"_id":121,"key":{"_id_":1},"ns":"CEILODB2.meter","name":"_id_","unique":true,"datatype":"CHAR(12) FOR BIT DATA","datalength":13000,"idxtype":"typemarker"}, {"v":0,"_id":131,"key":{"timestamp":-1},"ns":"CEILODB2.meter","name":"timestamp_idx","unique":false,"datatype":"TIMESTAMP","datalength":0,"idxtype":"function_na"}]

Also, I noticed that DB2 nosql can automatically create the suitable index type when you create an index on the collection which already has documents. We can make full use of this function to resolve this problem I think.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/147766

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/147766
Committed: https://git.openstack.org/cgit/openstack/ceilometer/commit/?id=b2fd1dee45c19477223286f8be2118e584d9b3eb
Submitter: Jenkins
Branch: master

commit b2fd1dee45c19477223286f8be2118e584d9b3eb
Author: lqslan <email address hidden>
Date: Fri Jan 16 11:31:55 2015 +0800

    [DB2 nosql] Create TIMESTAMP type index for 'timestamp' field

    Currently, when doing ceilometer-dbsync, ceilometer will create an
    index for 'timestamp' field of meter collection. But the datatype
    of the field is set to 'VARCHAR' which is not correct.

    The patch insert a document with 'timestamp' before creating the
    index of 'timestamp', then DB2 nosql will create the correct index
    type for 'timestamp' field.

    Change-Id: I69dd2fc8d552f5dbb2485c2a5eab55b3bee71e29
    Closes-Bug: #1411492

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/juno
Review: https://review.openstack.org/150223

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/150223
Committed: https://git.openstack.org/cgit/openstack/ceilometer/commit/?id=d5262707a9956c58db203c6b792ae94140588191
Submitter: Jenkins
Branch: stable/juno

commit d5262707a9956c58db203c6b792ae94140588191
Author: lqslan <email address hidden>
Date: Fri Jan 16 11:31:55 2015 +0800

    [DB2 nosql] Create TIMESTAMP type index for 'timestamp' field

    Currently, when doing ceilometer-dbsync, ceilometer will create an
    index for 'timestamp' field of meter collection. But the datatype
    of the field is set to 'VARCHAR' which is not correct.

    The patch insert a document with 'timestamp' before creating the
    index of 'timestamp', then DB2 nosql will create the correct index
    type for 'timestamp' field.

    Change-Id: I69dd2fc8d552f5dbb2485c2a5eab55b3bee71e29
    Closes-Bug: #1411492
    (cherry picked from commit b2fd1dee45c19477223286f8be2118e584d9b3eb)