[CALCITE-1920] Add IS_NOT_NULL predicate on not-nullable equi-join keys

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 1.13.0
• Assignee: Julian Hyde
• Reporter: Ted Xu
• Created: 03/Aug/17 01:52
• Updated: 03/Aug/17 08:15
• Resolved: 03/Aug/17 04:09

Description

In equi-joins, if the join keys are not-nullable according to join type, we can assign a IS_NOT_NULL predicate to reduce input. For example, query:

select * from src1 join src2 on src1.id = src2.id

can be rewrite to

select * from 
(select * from src1 where src1.id is not null) src1
join 
(select * from src2 where src2.id is not null) src2
on src1.id = src2.id

Issue Links

• is duplicated by: CALCITE-1526 Use Strong to infer whether a predicate's inputs may be null