Difference between TIMESTAMP and UNIQUEIDENTIFIER in SQL Server
S.NoTimestampUniqueIdentifier1Size of TIMESTAMP value is 8 bytes.Size of UNIQUEIDENTIFIER is 16 bytes. 2TIMESTAMP is not based on system date or time.UNIQUEIDENTIFIER value is based on the computer's MAC addresses and system date time. 3The purpose to TIMESTAMP is to track the operation in tables on the database level.The purpose of UNIQUEIDENTIFIER is to have a unique value assigned to a row (maybe as primary key). It remains unique in any system in the world.