albel727 commented on issue #4667: URL: https://github.com/apache/arrow-datafusion/issues/4667#issuecomment-1356838250
After a bit of experimenting, it doesn't seem like the bug is limited to selecting from `UNION`, but rather any `SELECT ... FROM (SELECT DISTINCT ... FROM ...)`. Which is apparently how `UNION` is implemented internally https://github.com/apache/arrow-datafusion/issues/998#issuecomment-923155977 E.g. the following also yields wrong results: ```sql SELECT DISTINCT * FROM tbl; ``` ``` +----+------+ | id | data | +----+------+ | 1 | 10 | | 1 | 20 | +----+------+ ``` ```sql SELECT id FROM (SELECT DISTINCT * FROM tbl); ``` ``` +----+ | id | +----+ | 1 | +----+ ``` Where it of course should have returned two rows. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
