zhangshenghang opened a new issue, #12523: URL: https://github.com/apache/seatunnel/issues/12523
### Description The Zeta SQL engine (`ZetaSQLEngine#project`) evaluates every select item through the general expression evaluator (`zetaSQLFunction.computeForValue`) for every row. For the very common projection-only statement ``` SELECT source_col AS target_col, ... FROM ... ``` each row still walks the full SQL expression machinery, although the statement is just a field reordering/renaming that could be resolved to fixed input field indexes once at plan time. Expected: when every select item is a plain column reference (no where/having/distinct, no functions, no wildcards), precompute the input field indexes and let `project` copy the fields directly. ### Impact Measurable CPU overhead on high-throughput jobs that use the SQL transform for column selection/renaming, which is one of the most common transform usages. -- 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]
