mysql trigger

hi,


That company wants to enforce the following logic when it comes to inserting new rows to the accounts table:
1)name must have at least 3 characters.
2) email must contain at least one @characters.

we try to build a trigger for it so that it signal '45000' as a SQLSTATE error without setting MESSAGE_TEXT, if either of those vaildation fail.

what should be the script of the trigger?