Module mz_transform::literal_constraints

See if there are predicates of the form <expr> = literal that can be sped up using an index. More specifically, look for an MFP on top of a Get, where the MFP has an appropriate filter, and the Get has a matching index. Convert these to IndexedFilter joins, which is a semi-join with a constant collection.

E.g.: Logically, we go from something like SELECT f1, f2, f3 FROM t WHERE t.f1 = lit1 AND t.f2 = lit2 to SELECT f1, f2, f3 FROM t, (SELECT * FROM (VALUES (lit1, lit2))) as filter_list WHERE t.f1 = filter_list.column1 AND t.f2 = filter_list.column2

Structs

• LiteralConstraints
  Convert literal constraints into IndexedFilter joins.

Enums

• IndexMatch 🔒
  Whether an index is usable to speed up a Filter with literal constraints.