Hi, Steve! On Tue, Sep 19, 2023 at 8:36 PM Steve Chavez <st...@supabase.io> wrote: > > Just to give a data point for the need of this function: > > https://dba.stackexchange.com/questions/231879/how-to-get-the-basetype-of-a-domain-in-pg-type > > This is also a common use case for services/extensions that require postgres > metadata for their correct functioning, like postgREST or pg_graphql. > > Here's a query for getting domain base types, taken from the postgREST > codebase: > https://github.com/PostgREST/postgrest/blob/531a183b44b36614224fda432335cdaa356b4a0a/src/PostgREST/SchemaCache.hs#L342-L364 > > So having `pg_basetype` would be really helpful in those cases. > > Looking forward to hearing any feedback. Or if this would be a bad idea.
I think this is a good idea. It's nice to have a simple (and fast) built-in function to call instead of investing complex queries over the system catalog. The one thing triggering my perfectionism is that the patch does two syscache lookups instead of one. In order to fit into one syscache lookup we could add "bool missing_ok" argument to getBaseTypeAndTypmod(). However, getBaseTypeAndTypmod() is heavily used in our codebase. So, changing its signature would be invasive. Could we invent getBaseTypeAndTypmodExtended() (ideas for a better name?) that does all the job and supports "bool missing_ok" argument, and have getBaseTypeAndTypmod() as a wrapper with the same signature? ------ Regards, Alexander Korotkov
