jackylee-ch opened a new pull request, #46958: URL: https://github.com/apache/spark/pull/46958
### What changes were proposed in this pull request? For some data sources, CHAR type padding is not applied on both the write and read sides (by disabling `spark.sql.readSideCharPadding`), as a different SQL flavor, which is similar to MySQL: https://dev.mysql.com/doc/refman/8.0/en/char.html However, there is a bug in Spark that we always pad the string literal when comparing CHAR type and STRING literals, which assumes the CHAR type columns are always padded, either on the write side or read side. This is not always true. This PR makes Spark always pad the CHAR type columns when comparing with string literals, to satisfy the CHAR type semantic. ### Why are the changes needed? bug fix if people disable read side char padding ### Does this PR introduce _any_ user-facing change? Yes. After this PR, comparing CHAR type with STRING literals follows the CHAR semantic, while before it mostly returns false. ### How was this patch tested? new tests ### 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]
