SQL server write once column

Question

Is there any way to configure a SQL server instance to not permit updates to values inserted in the database?

e.g. once inserted, the value is fixed, other columns in that same row may be changed, but that value is only written once.

Answer 1

Write a trigger on update that checks the current column against the new value being inserted and rolls back the transaction if the values differ.

create trigger dbo.tr_no_updates
on mytable
for update
as
if update(mycolumn)
   rollback transaction