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Published 20 hours ago • verified publisher icon zhouqingqing

we should realize the MarkJoin as HashJoin

Open 9DemonFox opened this issue 4 years ago • 2 comments

9DemonFox avatar Nov 13 '20 06:11 9DemonFox

When a markjoin deprived from IN clause, it can't be seen as a semi join, because there might be a "null".

9DemonFox avatar Nov 17 '20 03:11 9DemonFox

More precisely, EXIST, IN should use SEMI JOIN， but NOT IN is not SEMI JOIN. Understanding this , the work to simplefy markjoin can work on.

9DemonFox avatar Nov 17 '20 06:11 9DemonFox