[CALCITE-5466] Constant condition can't be reduced after correlate

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.33.0
• Component/s: core
• Labels: pull-request-available
• Assignee: WenJun Min
• Reporter: WenJun Min
• Created: 04/Jan/23 11:36
• Updated: 07/Feb/23 22:33
• Resolved: 20/Jan/23 03:28

Description

Currently the RelMdPredicates do not handle the predicates for the correlate node which will generate the below output

Sink(table=[default_catalog.default_database.sink_t], fields=[name, num])
+- Calc(select=[name, CAST(CASE(=(__source_type__, _UTF-16LE'bounded'), 1, 2) AS BIGINT) AS num])
   +- Correlate(invocation=[test_udtf($cor1.name)], correlate=[table(test_udtf($cor1.name))], select=[name,__source_type__,EXPR$0], rowType=[RecordType(VARCHAR(2147483647) name, CHAR(7) __source_type__, VARCHAR(2147483647) EXPR$0)], joinType=[INNER])
      +- Calc(select=[name, _UTF-16LE'bounded' AS __source_type__])
         +- TableSourceScan(table=[[default_catalog, default_database, source_t]], fields=[name])

However, the '_source_type_' is obviously a constant can be reduced during optimizing. It can be solved by extend the RelMdPredicates to get predicates from the left input of the correlate node

Issue Links

• links to: GitHub Pull Request #3035