Hi, > > > > OIDS are a system level implementation. They are no longer required > > > > (you can make tables without OIDS) and they may go away someday. What about tableoids? Are they from the same generator as row oids (and hence may suffer wrap-around)? Or are they unique across the db? I ask because I'm currently using them to join a single table to rows in arbitrary tables, something like: +-------------+ | JOINME | +-------------+ | foreign_oid | | foreign_id | | ... | +-------------+ Where foreign_oid is the tableoid of the table and foreign_id is the (serial, not oid) id of the row in that table. I dunno if it's bad design, but it's darn handy. M ---------------------------(end of broadcast)--------------------------- TIP 9: the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match