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Unnest IN/ANY/EXISTS subqueries and optimize them using semi-join algorithm

Open dyemanov opened this issue 1 year ago • 1 comments

The initial implementation was developed by customer request, later it was slightly improved and committed into a separate branch for testing. Some issues were found that prevented it from inclusion into v5.0. Still work in progress.

dyemanov avatar Apr 01 '24 14:04 dyemanov

A partial implementation (covering only equivalence conditions) is committed into v5.0.1, but disabled by default (see SubQueryConversion setting in firebird.conf).

dyemanov avatar Jul 31 '24 07:07 dyemanov

More complete implementation (enabled by default and so far without an option to disable it) is ready for v6. It adds a (limited but still) choice between nested loop and hash semi-join algorithms to be used. Optimization aspects are to be further improved in the master branch later.

dyemanov avatar Mar 03 '25 06:03 dyemanov