Procedures are procedures regardless of where they are written. In many aspects it can be mechanically more difficult to deal with SQL UDFs but that is a usab

Procedures are procedures regardless of where they are written. In many aspects it can be mechanically more difficult to deal with SQL UDFs but that is a usability weakness that just needs some more treatment rather than anything particularly fundamental, I feel. There are three common reasons I write UDFs: * The SQL type system and dependency tracking are deemed helpful. This applies only to 'LANGUAGE SQL' functions, which are just regular queries. Unlike dynamically generated SQL from the application, type checks and dependency tracking on other SQL objects can be employed. This is hard to address in any tooling without having a complete copy of the catalogs (and many databases are not as self-hosted complete as Postgres' catalogs, so sometimes that may not be enough...) and semantic analyzer. * Diverse language and/or library access. If there is a series of obscure rules to hold simple invariants locked into exactly one application's libraries, it makes it pretty much impossible to use any other library. This can be addressed, but it's often expensive to do so. * Performance, in rare cases where network round trip dominates execution time and I need more than one plain SQL statement; this is only the case for the integrated 'procedural' languages. One could accomplish something similar by running the application's code closer to the machine, and I think that'd be better, actually, but requires some orchestration.