Re: pessimal trivial-update performance

Robert Haas <robertmhaas@gmail.com> writes:
> CREATE OR REPLACE FUNCTION update_tab() RETURNS void AS $$
> BEGIN
> 	INSERT INTO tab VALUES (0);
> 	FOR i IN 1..100000 LOOP
> 		UPDATE tab SET x = x + 1;
> 	END LOOP;
> END
> $$ LANGUAGE plpgsql;

I believe that none of the dead row versions can be vacuumed during this
test.  So yes, it sucks, but is it representative of real-world cases?

			regards, tom lane