It turns out that it appears to be a data discrepancy that caused the query optimiser to, well, not optimise.
I thought the main table (r) with 3million records would be the problem, but it was table p with 3100 records on the live server and 3082 records on my dev pc that caused the problem. Although the results of show create table etc were identical on both machines, uploading the data from dev to live has solved the problem. Thanks to all that offered advice. Graham <snip size="big"/> -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]