Mike Christensen <mike@kitchenpc.com> writes:
> So are you saying that a JOIN can only refer to itself and the last
> table on the FROM list?
Um, I think you've got the wrong mental model of the syntax. JOIN
is a binary operation between two tables:
tab1 JOIN tab2 ON some-condition-involving-tab1-and-tab2-only
You can nest these critters (ie, tab1 or tab2 could itself be a
JOIN construct), and you can write them as elements of a comma-separated
FROM list. But the ON condition can never refer to anything outside
its JOIN construct.
regards, tom lane