disallow updates on column or whole table

Hi all,

What is the best way to disallow updates on a column of a table, or even
on a whole table itself?

I can write a BEFORE UPDATE trigger which compares old.column_name(s) to
new.column_name(s) and raise an exception if these values are different.

Are there better ways?

Certain properties cannot be changed once inserted. I would like to
enforce that in my database schema.

Thanks in advance. Kind regards,

Peter