select r.rdb$field_name, f.rdb$field_type, f.rdb$field_length,f.rdb$field_scale from rdb$relation_fields r, rdb$fields f where r.rdb$field_source = f.rdb$field_name and r.rdb$relation_name = '^0' order by r.rdb$field_position;
select rdb$relation_name from rdb$relations where rdb$system_flag = 0;