Non-cursor cursors

So I've been doing SQL queries for a while now, but only just worked out that 99 times out of 100, whenever you think you need a cursor, you probably don't. You probably need some sort of loop and some sort of track of where you are...but the answer to that is NOT a cursor.

For example:

You have a list of portfolios that you wish to value, but you need to call a proc/function against each in turn, so doing a single query is out of the question. The answer would appear to be a cursor, iterating over a list. WRONG.

Here's how NOT to do it:

DECLARE pfo_cursor CURSOR FOR
SELECT pfo FROM #id
OPEN pfo_cursor
FETCH NEXT FROM pfo_cursor INTO @pfoLoop
WHILE @@FETCH_STATUS = 0

...do stuff with @pfoLoop

FETCH NEXT FROM pfo_cursor INTO @pfoLoop
CLOSE
DEALLOCATE

And here's a quicker, easier, cheaper, better way:

SET @pfoLoop = (SELECT TOP 1 pfo FROM #id ORDER BY pfo)
WHILE @pfoLoop is not null
BEGIN
...do stuff with @pfoLoop
SET @pfoLoop = (SELECT TOP 1 pfo FROM #id WHERE pfo > @pfoLoop ORDER BY pfo)
END

Easier, non? Quicker non? No cursors!