morningman commented on PR #15614: URL: https://github.com/apache/doris/pull/15614#issuecomment-1371746489
> > Why we need hint to do this? This should be set automatically by optimizer? > > This hint is supported by the old planner currently. AFAIK, people can use this hint when the optimizer can't recognize the query could use pre-aggregation automatically, such as OLAP scan node in joins, subqueries or aggregate functions' input is not a slot reference but complex expressions. Ideally, pre-aggregation should be set by the optimizer. But this hint leaves a chance for users to enable pre-aggregation for cases that optimizer can't work well. OK, I see -- 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: commits-unsubscr...@doris.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@doris.apache.org For additional commands, e-mail: commits-h...@doris.apache.org
