I have never used MySQL but am guessing it is not like SQL for Oracle. My query says this:
update work_order
set row_num=(select max(row_num)+1 from work_order)
where row_num=5
and I am getting an error. Anyone know why?
Or maybe someone has an idea of how I can make a rownum in my table?
Thanks

Your MySQL version does not support subqueries. You should use the MySQL REPLACE if you have a unique index on your table.
http://www.mysql.com/doc/en/REPLACE.html

Got it working. Thanks.