Wrong Results when Query has Distinct Aggregate (sum(distinct <col>), count(distinct <col>) etc.) and Runs in Parallel
(Doc ID 2324896.1)
Last updated on JULY 01, 2021
Applies to:Oracle Database - Enterprise Edition - Version 220.127.116.11 to 18.104.22.168 [Release 12.1]
Oracle Database Cloud Schema Service - Version N/A and later
Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Information in this document applies to any platform.
- Wrong results in 12.1 when the query contains a distinct aggregation (such as sum(distinct <col>) or count(distinct <col>), etc.), and the query is run in parallel
- NULLs may be returned instead of correct values
- The plan will contain the operation PX SEND 1 SLAVE, as in the example below:
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