[IMPALA-12089] Be able to skip pushing down a subset of the predicates

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Done
• Component/s: Frontend
• Labels: impala-iceberg performance
• Epic Color: ghx-label-3
• Assignee: Peter Rozsa
• Reporter: Gabor Kaszab
• Created: 24/Apr/23 12:36
• Updated: 04/Jun/24 17:37
• Resolved: 29/Sep/23 06:30

Description

https://issues.apache.org/jira/browse/IMPALA-11701 introduced logic to skip pushing down predicates to Impala scanners if they are already applied by Iceberg and won't filter any further rows. This is an "all or nothing" approach where we either skip pushing down all the predicates or we push down all of them.

As a more sophisticated approach we should be able to push down a subset of the predicates to Impala Scan nodes. For this we should be able to map Iceberg predicates (returned from residual()) to Impala predicates. This might not be that trivial as Iceberg sometimes doesn't return the exact same predicates as it received through planFiles(). E.g. the object ID might be different making the mapping more difficult.

Issue Links

• causes: IMPALA-12580 Iceberg predicate filtering fails with UnsupportedOperationException