Re: programmatically retrieve details of a custom Postgres type

Thank you, Pavel and Tom! It works great!

On Thu, Nov 10, 2022 at 9:30 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> I wrote:
> > For a composite type, pg_type.typrelid links to pg_class and pg_attribute
> > entries that work much like a table.
>
> Actually, you could reverse that: for a table, pg_type.typrelid links to
> pg_class and pg_attribute entries that work much like a composite type.
>
> For both relations and composite types, there are pg_class and pg_type
> entries that (by convention only) have the same names and namespaces.
> They cross-link to each other via pg_class.reltype and pg_type.typrelid.
> The associated pg_attribute entries have attrelid matching the pg_class
> OID. The catalog entries for the two cases are pretty nearly
> indistinguishable except for pg_class.relkind. Again, it's only by
> convention that we consider that the pg_type entry is primary for a
> composite type but pg_class is primary for a relation.
>
> Of course, a relation has some underlying storage (for most relkinds),
> and it will likely have associated entries in other catalogs that a
> composite type won't. But the core catalog entries are about the same.
>
> regards, tom lane
>