findepi commented on code in PR #16859: URL: https://github.com/apache/datafusion/pull/16859#discussion_r2229264131
########## datafusion/functions/src/datetime/date_trunc.rs: ########## @@ -185,6 +187,21 @@ impl ScalarUDFImpl for DateTruncFunc { ) -> Result<ColumnarValue> { let parsed_tz = parse_tz(tz_opt)?; let array = as_primitive_array::<T>(array)?; + + // fast path for fine granularities + if matches!( + granularity.as_str(), + "second" | "minute" | "millisecond" | "microsecond" + ) || (parsed_tz.is_none() && granularity.as_str() == "hour") + { + let result = general_date_trunc_array_fine_granularity( Review Comment: You're right. For minute and smaller granularities the new code path is always fine¹ For hour it's also fine, for zone-less data. - (¹) in the past (early XX century and earlier) named zones often had offset changes not multiple of minutes at list this is what https://www.timeanddate.com/time/zone/nepal/kathmandu shows me. Not sure whether chrono respects that <img width="831" height="259" alt="image" src="https://github.com/user-attachments/assets/eea59fb7-02e2-4613-9be1-e248865b2a92" /> - for zone-less data (timestamp without time zone), day granularity can also be applied with just divide and mul, just like hour. Or am i blind again? -- 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: github-unsubscr...@datafusion.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For additional commands, e-mail: github-h...@datafusion.apache.org