[HIVE-22507] KeyWrapper comparator create field comparator instances at every comparison

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 4.0.0, 4.0.0-alpha-1
• Component/s: Physical Optimizer
• Assignee: Krisztian Kasa
• Reporter: Krisztian Kasa
• Created: 18/Nov/19 15:02
• Updated: 22/Mar/22 08:55
• Resolved: 27/Nov/19 07:23

Description

TopNKeyOperator.KeyWrapperComparator uses separate comparators for each field of the keys. Every time when TopNKeyOperator.KeyWrapperComparator.compare is called a new instance of the field operators are created.

The field comparators should be created prior any comparison. Probably in the constructor of KeyWrapperComparator or during initializeOp.

https://github.com/apache/hive/blob/fc81b8909b1a0e6aa15900387a98bccf38ae2247/serde/src/java/org/apache/hadoop/hive/serde2/objectinspector/ObjectInspectorUtils.java#L964
 

Issue Links

• is related to: HIVE-17896 TopNKey: Create a standalone vectorizable TopNKey operator
• links to: Review Board