Re: [PoC] XMLCast (SQL/XML X025)

Character data type in this sentence means the character types[1] as a
category, not the type character or character varying.

Interval is already part of the date/time types[1]

Not really. XMLCast implements the type-specific lexical and semantic
rules defined by SQL/XML, which apply only to base (non-domain) data
types. Although the grammar permits a domain name as a target, the
standard does not define any XML-specific semantics for domains.
Supporting them would go beyond the scope of this patch, and users
who need a domain can IMHO cast the XMLCast result afterward.