fix: group by expr not as column in step aggr

[discord9]

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What's changed and what's your intention?

fix a bug where group by exprs in upper aggr in step aggr failed to change to column refs, causing
step aggr to silently failed and cause wrong query plan(sliently!), fix:

• fail explicitly when transformer failed
• upper group by expr use column ref instead of original exprs
• also correctly deduce aggregate's original return type

PR Checklist

Please convert it to a draft if some of the following conditions are not met.

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.
• API changes are backward compatible.
• Schema or data changes are backward compatible.

[Copilot]

Pull Request Overview

This PR fixes a bug in step aggregation where GROUP BY expressions weren't properly converted to column references in upper aggregation nodes. The fix ensures that step aggregation fails explicitly when transformation fails and updates GROUP BY expressions to use column references instead of original expressions.

Key changes:

• Updated step aggregation transformation to use column references for GROUP BY expressions in upper nodes
• Modified error handling to fail explicitly when transformation fails instead of silently continuing
• Added more test data to validate the fix with additional query patterns

Reviewed Changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/common/function/src/aggrs/aggr_wrapper.rs	Fixes GROUP BY expressions to use column references in upper aggregation nodes
src/query/src/dist_plan/commutativity.rs	Updates transformer error handling to fail explicitly and propagate errors
src/query/src/dist_plan/analyzer.rs	Updates function signatures and error handling for transformer results
tests/cases/distributed/explain/step_aggr_basic.sql	Adds test data with more diverse host patterns
tests/cases/distributed/explain/step_aggr_basic.result	Updates expected results reflecting the test data changes
tests/cases/distributed/explain/step_aggr.sql	Adds new test cases for step aggregation validation
tests/cases/distributed/explain/step_aggr.result	Updates expected results for new test cases

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[waynexia]

LGTM

[evenyag]

fix a bug where group by exprs in upper aggr in step aggr failed to change to column refs, causing
step aggr to silently failed and cause wrong query plan(sliently!)

What's the wrong query plan generated without this fix?

[discord9]

fix a bug where group by exprs in upper aggr in step aggr failed to change to column refs, causing
step aggr to silently failed and cause wrong query plan(sliently!)

What's the wrong query plan generated without this fix?

i.e. for a group by date_bin('1s', ts) the upper plan (without this fix) will not change the group exprs,
but in fact it should use col("date_bin('1s', ts)") which is a column ref to the lower plan's output