[PIG-4377] Skewed outer join produce wrong result if a key is oversampled

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.15.0
• Component/s: impl
• Hadoop Flags: Reviewed
• Assignee: Daniel Dai
• Reporter: Daniel Dai
• Created: 09/Jan/15 21:38
• Updated: 18/Jan/16 17:27
• Resolved: 27/May/15 19:47

Description

Skewed outer join produce more than expected rows under certain condition. The extra rows contain null left relation. Can be reproduced reliably with reproduce.patch (run SkewedJoin_11).

Issue Links

• breaks: PIG-4587 Applying isFirstReduceOfKey for Skewed left outer join skips records
• breaks: PIG-4541 Skewed full outer join does not return records if any relation is empty. Outer join does not return any record if left relation is empty
• breaks: PIG-4580 Fix TestTezAutoParallelism.testSkewedJoinIncreaseParallelism test failure