How does MySQL handle concurrency control between two or more concurrent quires (not transactions), on their website they say they use multi-versioned concurrency control, but i guess this between transactions, not queries.
Consider the case we have two queries Q1: select * from table1 EXCEPT select * from table1 where id>50; Q2:update table1 set id = id+1; Concurrent execution of these two queries could result in incorrect results, if no appropriate concurrency control is used, specifically if the update query is executed between the first half of Q1 and the second half. there are many other examples to this problem, so i wonder how MySQL handles it. Thanks, Khaled. --------------------------------------------------------------------- Before posting, please check: http://www.mysql.com/manual.php (the manual) http://lists.mysql.com/ (the list archive) To request this thread, e-mail <[EMAIL PROTECTED]> To unsubscribe, e-mail <[EMAIL PROTECTED]> Trouble unsubscribing? Try: http://lists.mysql.com/php/unsubscribe.php
