Re: What is wrong with this query?

On 15 May 1995, Chuck Hamilton wrote:

> Date: 15 MAY 1995 21:30:01 GMT
> From: Chuck Hamilton <chuckh_at_ix.netcom.com>
> Newgroups: comp.databases.oracle
> Subject: Re: What is wrong with this query?
>
>
> 2. This select might be a bit faster...
>
> select bill_acct_id from transmission where not exists (select * from
> convert_acct where acct_id = transmission.bill_acct_id);
> --
> ><> Chuck Hamilton <><
> ><> chuckh_at_ix.netcom.com <><
Chuck,

        Doesn't that make for a co-related sub-query? Ie, the inner select has to be re-done for every row fetched in the outer query?

        I would think the original way would be faster, provided he indexed the convert_acct table correctly, and maybe added a 'distinct' to the sub query.

        Just askin....

Dave

David B Erickson, Project Leader     * 
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