Enforcing Locks (Magic xpa 3.x)
Explicit locking can be acquired at the same levels as implicit locking. When updating a record, an implicit exclusive lock is acquired at record level.
When initiating a
select * from table where ... for update
statement under Oracle, or a
select * from table (UPDLOCK NOWAIT) where …
statement under MSSQL, an explicit shared lock is acquired at record or page level, and the record cannot be updated until the lock is released.