Hi Krishna, Its the bottom-up approach in all db's which follow SQL standards. Can u please show us the explain plan of the below query.
regards anandkl On 8/14/07, krishna chandra prajapati <[EMAIL PROTECTED]> wrote: > > Hi all, > > i have to optimize complex join queries. i am not able to understand how > the complex queries gets executed. Whether it follow top-down or bottom-up > approach. There is millions of data. > > The queries is: > > select ucp.user_id as RESULTANT_ID from user_course_payment > ucp,crm_sales_contact sc, crm_contacts c where c.contact_id=sc.contact_id > and c.product_id = sc.product_id and sc.product_id=1 and > sc.resultant_id =ucp.user_id and sc.resultant_id !='' and > c.operator_id=1 and date_format(ucp.payment_date,'%Y-%m-%d') >= > '2001-12-12' and date_format(ucp.payment_date,'%Y-%m-%d') <= '2007-12-12' > GROUP BY > ucp.user_id; > > Please help me. > > -Regards, > Krishna > > >