[CALCITE-5639] RexSimplify should remove IS NOT NULL check when LIKE comparison is present

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 1.34.0
• Fix Version/s: 1.35.0
• Component/s: core
• Labels: pull-request-available
• Assignee: Leonid Chistov
• Reporter: Leonid Chistov
• Created: 11/Apr/23 12:55
• Updated: 27/Jul/23 10:22
• Resolved: 25/Apr/23 14:31

Description

Consider query like

select r_reason_desc from reason
where r_reason_desc is not null and r_reason_desc like '%child%' 

where "r_reason_desc" is a nullable field.

When RexSimplify::simplifyFilterPredicates is called on that conjunction of expressions, expression is not simplified, meaning that redundant  "is not null" check is not removed.

In the same time, if query like 

select r_reason_desc from reason
where r_reason_desc is not null and r_reason_desc >= 'A'

is passed to optimizer, redundant "is not null" check is eliminated.

Issue Links

• links to: GitHub Pull Request #3143