Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Usenet -> c.d.o.server -> Re: Apparently anomalous behaviour with a subquery - has anyone seen this?

Re: Apparently anomalous behaviour with a subquery - has anyone seen this?

From: Galen Boyer <galenboyer_at_hotpop.com>
Date: 10 Jul 2002 08:27:07 -0500
Message-ID: <uit3nd89w.fsf@grossprofit.com>


On Wed, 10 Jul 2002, richard.foote_at_bigpond.com wrote:

> The inner query is hence referencing a column from the outer
> query to create an equivalent predicate to 'where t1.id in
> (select t1.var from t2)'; (which is always false with this lack
> of data).
>
> Therefore the subquery is referencing the outer query therefore
> this is an example of a correlated subquery ?
>
> I'm beginning to get confused now :)

Me to. I can see how the query,

   select count(*) from t1 where id in (select var from t2);

could be considered a subquery, but var doesn't "join" to anything in t2, so what is it correlating on?

-- 
Galen Boyer
Received on Wed Jul 10 2002 - 08:27:07 CDT

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US