HeartSaVioR opened a new pull request, #45951: URL: https://github.com/apache/spark/pull/45951
### What changes were proposed in this pull request? This PR proposes to disallow using binary inequality collation column in the key schema of stateful operator. Worth noting that changing the collation for the same string column during the query restart was already disallowed at the time of introduction of collation. ### Why are the changes needed? state store API is heavily relying on the fact that provider implementation performs O(1)-like get and put operation. While the actual implementation would be dependent on the state store provider, it is intuitive to assume that these providers only do lookup of the key based on binary format (implying binary equality). That said, even though the column spec is case insensitive, state store API wouldn't take this into consideration, and lead to produce the wrong result. e.g. Counting 'a' and 'A' differently while the column is case insensitive. ### Does this PR introduce _any_ user-facing change? No, as it wasn't released yet. ### How was this patch tested? New UTs. ### Was this patch authored or co-authored using generative AI tooling? No. -- 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]
