morrySnow opened a new issue, #13616: URL: https://github.com/apache/doris/issues/13616
This issue is used to record the progress of the implementation of CTE functions and subtasks in nereids. Currently, the CTE syntax is implemented by fully inlining it(in #12742), without cost-based optimization. Based on approaches and algorithms in paper [Optimization of Common Table Expressions in MPP Database Systems](http://www.vldb.org/pvldb/vol8/p1704-elhelw.pdf), there are still a few more subtasks to be done, which may refactor the current CTE implementation. Subtasks for this issue: - [x] the completed CTE-related syntax, except keyword RECURSIVE, which is not supported in existing implementation; https://github.com/apache/doris/pull/12742 - [ ] data structures (and corresponding logical and physical operators, if necessary) for CTE, includes CTEProducer, CTEConsumer, CTEAnchor, Sequence; - [ ] transformation rules for CTE, includes anchorToNoOp, anchorToSequence, consumerToInlinedCTEPlan; - [ ] algorithm to check and eliminate invalid CTE derived plan(generated by CTE transformation rules); - [ ] optimization for CTEConsumer, includes predicate push down(specific to CTE), inline single-used CTEs, eliminate unused CTEs recursively; - [ ] choose the best CTE plan alternatives by CBO; - [ ] materialize results of CTEProducer, and deliver those results to corresponding CTEConsumer in correct order(to avoid deadlocks); -- 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.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
