[IMPALA-11536] Invalid push down predicates in outer join simplification

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Impala 4.0.0, Impala 4.1.0
• Fix Version/s: Impala 4.3.0
• Component/s: Frontend
• Target Version: Impala 4.3.0
• Epic Color: ghx-label-9
• Assignee: Xianqing He
• Reporter: Xianqing He
• Created: 25/Aug/22 06:45
• Updated: 29/May/23 01:48
• Resolved: 04/May/23 03:25

Description

When set ENABLE_OUTER_JOIN_TO_INNER_TRANSFORMATION = true;

It may invalid push down the predicate  that is not null rejecting in outer join simplification.

e.g.
SELECT COALESCE(jointbl.test_id, testtbl.id, dimtbl.id) AS id, test_zip,testtbl.zip
FROM functional.jointbl
FULL OUTER JOIN
functional.testtbl
ON jointbl.test_id = testtbl.id
FULL OUTER JOIN
functional.dimtbl
ON coalesce(jointbl.test_id, testtbl.id) = dimtbl.id
WHERE
`jointbl`.`test_zip` = 94611 and coalesce(`testtbl`.`zip`, 0) = 0;

 

 

We can't push down the predicate 'coalesce(testtbl.zip, 0) = 0' to ScanNode since it is not null rejecting

 

 

 

 

Issue Links

• is related to: IMPALA-5022 Outer join simplification