[CALCITE-6447] Extract common expressions for disjunctions in Join - ASF JIRA

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For SQL:

select *
from tbl_a
  join tbl_b on tbl_a.id = tbl_b.id
where (tbl_a.x > 100 and tbl_b.y < 10)
   or (tbl_a.x > 100 and tbl_b.z > 20)

we can rewrite it to

select *
from tbl_a
  join tbl_b on tbl_a.id = tbl_b.id
where tbl_a.x > 100
  and (tbl_b.y < 10 or tbl_b.z > 20)

And in this way tbl_a.x > 100 can be pushed down and it is likely that this will help reduce the amount of data involved in the join.

is related to

CALCITE-399 Factorize common AND factors out of OR predicates

CALCITE-394 Add RexUtil.toCnf, to convert expressions to conjunctive normal form (CNF)

links to

GitHub Pull Request #3832