Gabriel39 commented on pull request #6861: URL: https://github.com/apache/incubator-doris/pull/6861#issuecomment-955185605
> The reason why we have to block to wait for the arrival of the filter is that there is no ability to dynamically push down predicates on the scan. This is the first thing we need to address, rather than forcing down-push expressions. > > The ability to index may not be available without pushing down expressions. Also the segment layer will use the zone map index when init is called for the first time, so this is the first thing we do. > > If the olap scan node does not wait for any runtime filter, then there seems to be no benefit in the current implementation. If it does not wait for a runtime filter to arrive it means that the query has a higher probability of being a big query. The overhead of waiting at this time is not significant compared to the overall overhead. > > So we need to provide the ability to normailize predicates on the runtime filter. This way there is no need to wait for the filter to be sent Hi @stdpain I think you misunderstood me. In this PR, scan node will still execute only after the runtime filter is ready, so in essence, it just changes the place of the blocking for RF from join node to scan node. That is to say, scan node does not change its behavior after this PR. It still step by step to init , wait for RF arrival, and execute. -- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
