Added transitive closure transformation to Catalyst #11777
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What changes were proposed in this pull request?
A relatively simple transformation is missing from Catalyst's arsenal - generation of transitive predicates. For instance, if you have got the following query:
select * from table1 t1 join table2 t2 on t1.a = t2.b where t1.a = 42then it is a fair assumption that t2.b also equals 42 hence an additional predicate could be generated. The additional predicate could in turn be pushed down through the join and improve performance of the whole query by filtering out the data before joining it.
Such a transformation exists in Oracle DB.
Please note, in this PR a transitive predicate would be created for the following operations:
How was this patch tested?
I've added a new TransitiveClosureSuite with a series of unit tests