Alvaro Herrera <alvherre@xxxxxxxxxxxxxxxxx> writes: > Felix Kater wrote: >> I need a unique ID across all columns I create. Is it o.k. to >> achive this by combining pg_attribute.attnum of a column together with >> the OID of the table the column is in? > Yes, the table OID is unique, and pg_attribute.attnum is unique as well. > They are not reused, not even when columns are dropped. The OID could be re-used after the table is dropped, though. It's not clear whether Felix needs uniqueness across time or just at any one instant. regards, tom lane
