Hi guys,

When I do a MySQL dump for backup, should I STOP MySQL first?

If I do, service will be interrupted.
But if I dont, is the data more likely to be corrupted?

Pleasse shed a light on this. Thanks in advance

If you mean stop the MySQL service then no, you can't. What you can do is lock the tables or entire databases to disallow others to access during the dump then unlock them afterwards. This can be done via a mysqldump parameter. The manual tells you all about it.