Fix nullAllowed of Domain for identical operator in UtcConstraintExtractor

[hqbhoho]

Description

if (functionName.equals(IDENTICAL_OPERATOR_FUNCTION_NAME)) {
 return Optional.of(Domain.create(ValueSet.ofRanges(Range.range(type, startOfDate, true, startOfNextDate, false)), true));
}

Since IDENTICAL_OPERATOR_FUNCTION_NAME resolves to a range query (>=startOfDate AND <startOfNextDate), which is designed to match a specific date interval, the nullAllowed parameter would be set to false.

Additional context and related issues

Release notes

( ) This is not user-visible or is docs only, and no release notes are required.
( ) Release notes are required. Please propose a release note for me.
(X) Release notes are required, with the following suggested text:

## Iceberg/Delta Lake/MySQL/PostgreSQL
* Fix incorrect results due to incorrect pushdown of `IS NOT DISTINCT FROM`. ({issue}`27213`)

[findepi]

Would be good to add a jdoc to IDENTICAL_OPERATOR_FUNCTION_NAME documenting semantics (like SQL's NOT DISTINCT FROM, i assume)

[hqbhoho]

Yes,$identical is equal to IS NOT DISTINCT FROM for SQL.

IDENTICAL(IDENTICAL_OPERATOR_FUNCTION_NAME, "IS NOT DISTINCT FROM"),

https://github.com/trinodb/trino/blob/3f97a0f867df966de09c93004af5161cec7716db/plugin/trino-base-jdbc/src/main/java/io/trino/plugin/jdbc/expression/ComparisonOperator.java#L41C71-L41C72

[findepi]

it would be great to document it where io.trino.spi.expression.StandardFunctions#IDENTICAL_OPERATOR_FUNCTION_NAME is defined.

[hqbhoho]

I have added a jdoc like:
$identical function is equivalent to the SQL operator "IS NOT DISTINCT FROM".

[findepi]

Merged, thanks!

[chenjian2664]

@findepi @hqbhoho I think this PR probably deserves a release note, could you check if we should add one?

[hqbhoho]

@findepi @hqbhoho I think this PR probably deserves a release note, could you check if we should add one?

@chenjian2664 @findepi PTAL, I have added a release note.

[findepi]

I don't think it should cause incorrect query results.
I thought it is a small perf improvement in predicate pushdown, allowing us to filter better.

Please clarify.

Also, if this did indeed cause incorrect query results, would you mind adding a regression test that would show that correctness issue in plain sight (if applied before the fix was applied)?

[hqbhoho]

@findepi I have added a test to show incorrect query results, #27242

[findepi]

@chenjian2664 i suggest following RN

* Fix incorrect results due to incorrect pushdown of `IS [NOT] DISTINCT FROM`.  

this applies to Iceberg, Delta, PostgreSQL, MySQL

[hqbhoho]

@chenjian2664 i suggest following RN

* Fix incorrect results due to incorrect pushdown of `IS [NOT] DISTINCT FROM`.  

this applies to Iceberg, Delta, PostgreSQL, MySQL

I think maybe only IS NOT DISTINCT FROM will query incorrect results,IS DISTINCT FROM is equal to $not($identical()) will not pushdown in UtcConstraintExtractor.

[chenjian2664]

Thanks both!