True, if you explicitly use group by and order by, there would a group operation after which sorting happens, but the same would happen if you use just "GROUP BY". That how mysql works.
On 6/25/08, Jerry Schwartz <[EMAIL PROTECTED]> wrote: > > *From:* Ananda Kumar [mailto:[EMAIL PROTECTED] > *Sent:* Tuesday, June 24, 2008 10:50 PM > *To:* Jerry Schwartz > *Cc:* mysql@lists.mysql.com > *Subject:* Re: Very large temporary file(s) > > > > In mysql, GROUP BY also by default does sorting using "ORDER BY", so you an > avoid it by including "ORDER BY NULL" after GROUP BY, this should help. > > *[JS] Huh. I would think that using an explicit ORDER BY with a GROUP BY > would normally result in two sorts: one to do the grouping, and another to > order the results after the grouping operation.* > > * * > > *I will give it a try.* > > > > > > On 6/24/08, *Jerry Schwartz* <[EMAIL PROTECTED]> wrote: > > <sigh> In all of that information, I forgot to post the actual query: > > INSERT INTO consolidated_customer_data > SELECT > customers.customer_id, > account.account_name, > customers.email, > customers.email_status, > customers.dm_status, > customers.status, > customers.last_name, > customers.first_name, > customers.sal, > customers.company, > customers.address_1, > customers.address_2, > customers.address_3, > customers.country, > customers.zip, > customers.input_source, > customers.interest_category, > customers.interest_subcategory, > CONCAT("|", GROUP_CONCAT(cust_topics.topic_code SEPARATOR "|"), "|") > > AS topic_list, > stage.stage_name > FROM > customers JOIN account ON account.account_id = customers.account_id > JOIN stage ON customers.stage_id = stage.stage_id > LEFT JOIN cust_topics ON customers.customer_id = > cust_topics.customer_id > GROUP BY customers.customer_id; > > Regards, > > Jerry Schwartz > The Infoshop by Global Information Incorporated > 195 Farmington Ave. > Farmington, CT 06032 > > 860.674.8796 / FAX: 860.674.8341 > > www.the-infoshop.com > www.giiexpress.com > www.etudes-marche.com > > > > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED] > > >
