7.0.3 select/join syntax?

i've been perusing the source code for Aparthia (it's a mod_perl
and HTML::Mason website framework that hooks into postgresql)
which contained some perl stuff like

my $st = $dbh->prepare("SELECT a.auction_id,a.title,f.grade,f.comment, login(f.person_id)
    FROM forum f join auction a on (auction_id)
    WHERE f.auction_id = ? and f.person_id = ?");

i can't find "JOIN" in the documentation i've got (for 7.0.3)
regarding the SELECT statement...

select
    a.auction_id,
    a.title,
    f.grade,
    f.comment,
    login(f.person_id)
from
    forum f
    JOIN auction a ON (auction_id) -- say what?
where
    f.auction_id = ?
    and
    f.person_id = ?

i presume that basically adds a WHERE clause like
    forum f join auction a on (auction_id)
    ==
    where f.auction_id = a.auction_id
? (i could be wrong, i suppose.)

which i tried on some of my databases, and what i get instead is
"ambiguous"--

    > select e.name,t.name from _edu e join _topic t on (id);
    ERROR:  Column 'id' is ambiguous

are there some unreleased docs that detail this feature?

--
I figure: if a man's gonna gamble, may as well do it
without plowing.   -- Bama Dillert, "Some Came Running"

will@serensoft.com
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