Updating a field in mysql... Plz help

Hi,

I have two tables “s” and “a”, from which i need to append “Dolby” at the start of the “type” field in “a” table for all fields in table “s” having “Dolby” in location field of “s” table. How do i update the “a” table?

I have written the update statement, but its not working…

update a set type = concat(‘Dolby’,type) where type=“AC3” and location like ‘%Dolby%’’ right join s on (s.sid=a.sid);

Thanks,
Ramki