starocean999 opened a new pull request, #65846: URL: https://github.com/apache/doris/pull/65846
### What problem does this PR solve? Issue Number: close #xxx Related PR: https://github.com/apache/doris/pull/48502 Problem Summary: When an aggregate function has more than one child expression (e.g., [count(distinct k6, v7)](vscode-file://vscode-app/usr/share/code/resources/app/out/vs/code/electron-browser/workbench/workbench.html)), the pre-aggregation status check previously only handled the cases of zero children or exactly one child. Multi-child aggregate functions fell through to the else branch that attempted to process them via [checkAggWithKeyAndValueSlots](vscode-file://vscode-app/usr/share/code/resources/app/out/vs/code/electron-browser/workbench/workbench.html), which is designed for single aggregate functions with complex expressions like IF/CASE WHEN — not for genuinely multi-parameter aggregate functions. This could lead to incorrect pre-aggregation decisions for functions like COUNT(DISTINCT col1, col2). This fix explicitly rejects pre-aggregation for any aggregate function with more than one child, since Doris's storage engine does not support pre-aggregating multi-column distinct counts or other multi-parameter aggregate functions. None ### Check List (For Author) - Test <!-- At least one of them must be included. --> - [ ] Regression test - [ ] Unit Test - [ ] Manual test (add detailed scripts or steps below) - [ ] No need to test or manual test. Explain why: - [ ] This is a refactor/code format and no logic has been changed. - [ ] Previous test can cover this change. - [ ] No code files have been changed. - [ ] Other reason <!-- Add your reason? --> - Behavior changed: - [ ] No. - [ ] Yes. <!-- Explain the behavior change --> - Does this need documentation? - [ ] No. - [ ] Yes. <!-- Add document PR link here. eg: https://github.com/apache/doris-website/pull/1214 --> ### Check List (For Reviewer who merge this PR) - [ ] Confirm the release note - [ ] Confirm test cases - [ ] Confirm document - [ ] Add branch pick label <!-- Add branch pick label that this PR should merge into --> -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
