You are right. I didn't remember the semantics, and Oracle's rownum would not have been helpful. But the new row_number() in 8.4 would probably do the trick (though I use 8.3.7 :-( )
Also PG does not have a concept of an auto-increment pseudo-column like Oracle's "rownum". Any suggestions?
not true - it has sequences, and pseudo type serial. Rtfm!.
AIUI, rownum applies numbering to output rows in a SELECT statement, rather than some actual column of the table, which is likely what the OP is getting at.