[CALCITE-5162] RelMdUniqueKeys can return more precise unique keys for Aggregate

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.31.0
• Labels: pull-request-available
• Assignee: Chunwei Lei
• Reporter: Chunwei Lei
• Created: 20/May/22 03:17
• Updated: 03/Aug/22 16:21
• Resolved: 30/May/22 01:45

Description

Currently, RelMdUniqueKeys always returns group by keys as the unique key. However, it can return more precise unique keys by looking through group by keys. For instance:

select deptno, deptname, count(*) from dept group by deptno, deptname;

RelMdUniqueKeys can return deptno as the unique key instead of (deptno, deptname) if deptno is unique.

Issue Links

• links to: GitHub Pull Request #2816