Is there any way to trim data automatically Lets I have a table named myTable in mysql with Three field

1. id int autoincrement
2. product_id varchar(20) not null
3. product_name varchar(200) not null


Now I want to keep data in product_id and product_name without white-space.
Yes, one way to do this will be to create a insert trigger on the table...can trim the values before inserting into the table ..