seddonm1 commented on pull request #8966: URL: https://github.com/apache/arrow/pull/8966#issuecomment-749156346
> @seddonm1 , the API for built-in functions is relatively new and WIP. If you felt that it did not suit the needs or that it could be simpler / easier to use, please raise that concern. We anticipate that it will be more used as time progresses, and it is useful to check its design from time to time to make sure that its assumptions still hold. The instructions in the README are definitely enough information to easily add these kind of functions (I updated slightly) and I think the API (like the `Variadic` and `Uniform` signatures) is really intuitive - so I think you did a great job. The big question at a project level is which dialect of SQL to support. Adding `ltrim` for example is trivial but that is a Postgres specific function: https://www.postgresql.org/docs/13/functions-string.html#FUNCTIONS-STRING-OTHER (its in lots of other implementations too). If we decide Postgres support then already the DataFusion `concat` implementation does not align with Postgres in how it handles `null`. ---------------------------------------------------------------- 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. For queries about this service, please contact Infrastructure at: [email protected]
