Unnest IN/ANY/EXISTS subqueries and optimize them using semi-join algorithm #8061
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…eimplemented support for semi/anti joins inside the nested loop algorithm. Slightly changed implementation of full outer joins. Added transformation of IN/EXISTS subqueries into lateral semi-joins. Basic optimizer support for semi-joins. More efficient optimization for cross joins. Added some debug info (hash table statistics) for hash joins.
…, this allows expression-based hashing
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A partial implementation (covering only equivalence conditions) is committed into v5.0.1, but disabled by default (see |
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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.