You also need to watch foreign keys for other related tables. In this case it sounds like there were no interrelationships. But if data were deleted from a parent table, and then a child table, you would need to track and maintain the primary key on the parent during the "restore" insert so that you could correctly link up the child back to the parent's primary key. In that case, it would be easier to turn the IDENTITY_INSERT ON so that the records would flow smoothly back into the database from the backup copy, maintaining their key values. Another case where IDENTITY_INSERT might be a preferred solution is if the end user knew the primary key values and referenced them (like an account number). In that case, it would also be important to preserve the original key values.