Bugs item #2549582, was opened at 2009-01-30 17:43 Message generated for change (Tracker Item Submitted) made by Item Submitter You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=482468&aid=2549582&group_id=56967
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Core Group: MonetDB4 "stable" Status: Open Resolution: None Priority: 5 Private: No Submitted By: Jan Rittinger (tsheyar) Assigned to: Nobody/Anonymous (nobody) Summary: M4: leftthetajoin estimate way to small Initial Comment: In Pathfinder generated code the PROC htordered_unique_thetajoin() calls the COMMAND leftthetajoin (located in malalgebra.mx:248). The size estimate there is 'MIN(BATcount(l), BATcount(r)' which is completely different to all other thetajoin estimates in the MonetDB code. (In my case |l|=4728, |r|=12000, and the result contains 7586008 rows. Thus using leftthetajoin costs > 60 seconds whereas using nlthetajoin---based on the same underlying primitive---takes only 2 seconds.) BTW all other thetajoins ask for an explicit estimate. As this is however a stable branch I'm not sure whether the signature should be changed. Please let me know if there is no easy and meaningful solution. Then I will just replace the leftthetajoin call in the pathfinder code base. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=482468&aid=2549582&group_id=56967 ------------------------------------------------------------------------------ This SF.net email is sponsored by: SourcForge Community SourceForge wants to tell your story. http://p.sf.net/sfu/sf-spreadtheword _______________________________________________ Monetdb-bugs mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/monetdb-bugs
