xiedeyantu commented on PR #21088: URL: https://github.com/apache/datafusion/pull/21088#issuecomment-4133910311
I have one minor question. In the scenario of rewriting "g, count(distinct lower(a))" to "group by g, lower(a)", why restrict it to only "lower", "upper", and "cast"? I don’t think any restriction is needed here. If the intention is to express an injective function, then "lower" is not one. If it is an injective function, the rewrite could simply be "group by g, a". Could you please clarify the design rationale behind this? -- 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]
