Re: How do I create unique IDs for an existing set of records

"Nick Fankhauser"  writes:
> I tried:

> update test set new_pk = (select nextval('test_new_pk_seq'));

> but it wants to update *all* of the rows to the current nextval (I was
> hoping it would evaluate nextval on each row).

Yeah, the sub-select is taken (perhaps mistakenly) as something that
can be evaluated only once, because it doesn't depend on the outer
query.  You are overthinking the problem; this should work:

update test set new_pk = nextval('test_new_pk_seq');
		regards, tom lane