How to lock a row when updating data with ASP and SQL.

I use a form to update existing data, how to be sure that during the new
values are entered, nobody will read the same ones and try to change them.
Is it possible to lock a row between the SQL select statement and the SQL
update statement, so nobody else could also change them.

I saw the adLockPessimistic, but it does not seem to be adapt to with sql
statement.

I thank you in advance for your help

Christophe