Re: BUG #5926: information schema dtd_identifier for element_types, columns, parameters views inconsistent

On ons, 2011-06-08 at 11:09 -0400, Tom Lane wrote:
> As far as I can tell from the spec, dtd_identifier
> ought to be the identifier of the element type, while
> collection_type_identifier should be a made-up identifier for the
> array type.  That would make the sample query given in the docs
> correct.

But it's collection_type_identifier that you join against, say, columns,
so you can resolve the element type of column types.  So
collection_type_identifier must match the dtd_identifier schema of
columns etc., whereas element_types.dtd_identifier is not joinable
against anything.