alamb opened a new issue, #17152: URL: https://github.com/apache/datafusion/issues/17152
### Is your feature request related to a problem or challenge? - While reviewing https://github.com/apache/datafusion/pull/15361 I noticed that the `to_char` implementation for arrays could likely be improved substntially Specifically the code that The use of `Vec<Option<String>>` to build a string array is non ideal as it requires additional allocations for each output row along with a second copy of the data ```rust fn to_char_array(args: &[ColumnarValue]) -> Result<ColumnarValue> { let arrays = ColumnarValue::values_to_arrays(args)?; let mut results: Vec<Option<String>> = vec![]; // <--- this is non ideal ``` Also, the code that falls back to date formatting calls `cast` for a single row every time the formatting fails -- since the failure is likely due to a date specifier that will get called for all rows, it would probably be faster to convert the entire input array to `Date` once the first time the specifier is retried ### Describe the solution you'd like Make to_char faster You can evaluate your changes with the existing benchmark ```shell cargo bench --bench to_char ``` ### Describe alternatives you've considered _No response_ ### Additional context _No response_ -- 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.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
