Shekharrajak opened a new pull request, #2994: URL: https://github.com/apache/datafusion-comet/pull/2994
## Which issue does this PR close? Closes #2894 ## Rationale for this change Comet currently falls back to Spark for ALL final hash aggregates when there's no Comet partial aggregate in the child plan. This is overly conservative because some aggregates have compatible intermediate buffer formats between Spark and Comet. For example, MIN, MAX, COUNT, and bitwise aggregates (BIT_AND, BIT_OR, BIT_XOR) have simple intermediate buffers (single value) that are compatible between Spark and Comet. These can safely run with "Spark partial / Comet final" execution. Other aggregates like SUM, AVG, VARIANCE, etc. have known incompatibilities (e.g., decimal overflow handling differences, complex intermediate buffers) and should continue to fall back when there's no Comet partial aggregate. ## What changes are included in this PR? Added supportsSparkPartialCometFinal method to CometAggregateExpressionSerde trait - Default is false Added helper function - aggSupportsMixedExecution() in QueryPlanSerde ## How are these changes tested? "CometExecRule should not allow Spark partial and Comet final for unsafe aggregates" - Verifies SUM still falls back to Spark "CometExecRule should allow Spark partial and Comet final for safe aggregates" - Verifies MIN/MAX/COUNT can use Comet final with Spark partial -- 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]
