C++: Fix join order in CommentedOutCode#243
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adityasharad merged 1 commit intogithub:rc/1.18from Sep 27, 2018
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After the recent inlining of `unresolveElement`, the join order in `CommentedOutCode` became a problem. The join orderer was tempted to join the two `hasLocationInfo` calls first because they had one column in common. With this commit, they have no columns in common. It follows from the other predicates in the same file that this column would be the same, so there is no need to assert it in this predicate and risk that the join orderer uses that information. On Wireshark, the `CommentBlock::hasLocationInfo` predicate goes from taking 2m2s to taking 180ms. The query produces the same 7,448 alerts.
ian-semmle
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Sep 27, 2018
smowton
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Feb 7, 2022
Fix merge conflict
MathiasVP
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Aug 10, 2025
fix powershell qhelp files
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After the recent inlining of
unresolveElement, the join order inCommentedOutCodebecame a problem. The join orderer was tempted to join the twohasLocationInfocalls first because they had one column in common. With this commit, they have no columns in common. It follows from the other predicates in the same file that this column would be the same, so there is no need to assert it in this predicate and risk that the join orderer uses that information.On Wireshark, the
CommentBlock::hasLocationInfopredicate goes from taking 2m2s to taking 180ms. The query produces the same 7,448 alerts.