SET DURABILITY sets the transaction durability level.
▪STRICT means that as soon as a transaction is committed, the server writes the information to the transaction log file.
▪RELAXED means that the server may not write the information as soon as the transaction is committed; instead, the server may wait, for example, until it is less busy, or until it can write multiple transactions in a single write operation. If you use relaxed durability and the server shuts down abnormally, you may lose a few of the most recent transactions.
▪DEFAULT means that the durability level defined with the Logging.DurabilityLevel parameter is used.