Re: simple (?) join

On Thu, 24 Sep 2009 16:16:36 +0100, Gary Stainburn wrote about [SQL]
simple (?) join:

>create table orders (
>o_id serial primary key
>...
>);
>
>create table orders_log (
>ol_id serial primary key,
>o_id int4 not null references orders(o_id),
>ol_timestamp timestamp,
>ol_user,
>);
>
>How can I select all from orders and the last (latest) entry from the
>orders_log?

SELECT * FROM orders
WHERE o_id IN (SELECT o_id FROM orders_log
WHERE ol_timestamp = (SELECT MAX(ol_timestamp) FROM orders_log));

No joins required.
--
Regards,

Dave [RLU #314465]
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david(dot)w(dot)noon(at)ntlworld(dot)com (David W Noon)
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