Re: User defined I/O conversion casts

Heikki Linnakangas <heikki.linnakangas@enterprisedb.com> writes:
> Yeah, a magical OID clearly has some issues. A new field in pg_cast is 
> the obvious alternative. How about adding a "castmethod" char field, 
> with values:
> b = binary-compatible cast (CREATE CAST ... WITHOUT FUNCTION)
> i = I/O coercion cast (the new beast, CREATE CAST ... WITH INOUT)
> f = use cast function specified in castfunc field.
> castfunc is 0 for methods b and i.

Seems sane to me.  If you do that, please add a check in the opr_sanity
regression test that castfunc is nonzero if and only if castmethod is f.
        regards, tom lane