galaxytemple commented on code in PR #27347: URL: https://github.com/apache/datafusion/pull/27347#discussion_r4556401225
########## datafusion/physical-expr/src/equivalence/properties/union.rs: ########## Review Comment: Thanks for the question @vinycalves! 1. Aliases: `calculate_union` normalizes columns using their position index (col.index()) via `with_new_schema`. So even if different arms use different aliases, they get mapped to the same union output columns. 2. Casts: `UnionExec` requires all inputs to have matching data types. Before this function, `TypeCoercion` already aligns them by inserting necessary casts (e.g. casting Int to BigInt). I've also added a test case in `union.slt` verifying that union inputs with mismatched aliases and casts. -- 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]
