paramtype (PGresult)

    /*
     * call-seq:
     *    res.paramtype( param_number ) -> Oid
     *
     * Returns the Oid of the data type of parameter _param_number_.
     * Only useful for the result returned by conn.describePrepared
     */
    static VALUE
    pgresult_paramtype(VALUE self, VALUE param_number)
    {
            PGresult *result;

            result = get_pgresult(self);
            return INT2FIX(PQparamtype(result,NUM2INT(param_number)));
    }