HIVE-28757: Preserve partition create time

[myg821561935]

Supersedes #6628. GitHub closed the earlier PR automatically when its source branch was renamed; the commit itself is unchanged.

What changes were proposed in this pull request?

Keep the Partition objects returned by HMS in the single-partition and batch dynamic-partition load paths. The batch path now requests the partitions returned by add_partitions and uses them in the result map.

On the metastore side, preserve the existing partition createTime when an alter request carries an unset or non-positive value. This covers single, rename, and batch alter paths.

Regression tests were added for both the load and alter cases.

Why are the changes needed?

HMS assigns server-owned fields such as createTime when a partition is added. The load path currently discards the partition returned by HMS and keeps using the request-side object, whose createTime is still zero. A later statistics update can send that object through alter_partition and overwrite the value stored by HMS with zero.

This makes the partition creation time unreliable for retention and lifecycle management.

Does this PR introduce any user-facing change?

Yes. A newly created partition keeps the creation time assigned by HMS instead of having it reset to zero by a later alter operation. There is no public API change.

How was this patch tested?

• TestHiveLoadPartitionKeepExisting: 5 tests passed, including the new static and dynamic partition cases.
• TestAlterPartitions: 154 tests passed, including the new single and batch alter cases.
• The related 21-module Maven reactor completed successfully with JDK 21.

JIRA: https://issues.apache.org/jira/browse/HIVE-28757

[sonarqubecloud]

Quality Gate passed

Issues
11 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud