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

• Type: New Feature
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 1.37.0
• Fix Version/s: 1.37.0
• Component/s: core
• Labels: pull-request-available
• Assignee: Unassigned
• Reporter: ruanhui
• Created: 23/Jun/24 16:09
• Updated: 27/Jun/24 07:52

Description

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.

Issue Links

• is related to: CALCITE-399 Factorize common AND factors out of OR predicates
• is related to: CALCITE-394 Add RexUtil.toCnf, to convert expressions to conjunctive normal form (CNF)
• links to: GitHub Pull Request #3832