Is a sub-select more efficient than an outer join? SELECT cust_id FROM customers LEFT JOIN orders on customers.cust_id = orders.cust_id WHERE orders.cust_id IS NULL;
Or am I missing something (as usual)? Regards, Jerry Schwartz Global Information Incorporated 195 Farmington Ave. Farmington, CT 06032 860.674.8796 / FAX: 860.674.8341 > -----Original Message----- > From: Waldemar Jankowski [mailto:[EMAIL PROTECTED] > Sent: Friday, October 20, 2006 1:53 PM > To: [EMAIL PROTECTED] > Cc: mysql@lists.mysql.com > Subject: Re: help with query: select customers that ARO NOT > in orders table > > On Fri, 20 Oct 2006, [EMAIL PROTECTED] wrote: > > > hi to all, > > I have table customers (PK cust_id) > > I have table orders (PK order_id, FK cust_id) > > > > I need query that will selecct all customers from > 'customers' they don't > > have any order, there is not their cust_id in 'orders'. > > > > couls somebody help me? > > > > thanks. > > > > -afan > > I think the most explicit way is with a sub select: > > select cust_id from customers where > cust_id not in > (select cust_id from orders); > > -w > > > -- > > MySQL General Mailing List > > For list archives: http://lists.mysql.com/mysql > > To unsubscribe: > http://lists.mysql.com/[EMAIL PROTECTED] > > > > > > > > -- > MySQL General Mailing List > For list archives: http://lists.mysql.com/mysql > To unsubscribe: > http://lists.mysql.com/[EMAIL PROTECTED] > > -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
