Write once, read many mysql field

Question

Can you restrict a field from being updated without granting any additional user privileges ?

Basically a value in a row can only be set during an insert statement.

Answer 1

Yes. If you grant only insert and select privileges. Like:

grant select, insert, update(message, time) on hibtest.message to 'worm'@'localhost' identified by 'worm'

... this way the user can only update message and time columns.

Answer 2

You can use an update trigger to prevent the value from being updated.