TAILIEUCHUNG - Microsoft SQL Server 2008 R2 Unleashed- P45

Microsoft SQL Server 2008 R2 Unleashed- P45:SQL Server 2005 provided a number of significant new features and enhancements over what was available in SQL Server 2000. This is not too surprising considering there was a five-year gap between these major SQL Server 2008 is not as much of a quantum leap forward from SQL Server 2005 | 384 CHAPTER 14 Database Backup and Restore terms of server overhead because every transaction is captured and retained in the transaction log so that they can be recovered in the event of a failure. TIP A common problem in SQL Server environments involves a database that is set to full recovery but whose transaction log is never backed up. In this scenario the transaction log can grow to the point that it fills up the drive on which the transaction log is located. You need to ensure that you have regularly scheduled backups of the transaction log if you have set your database to full recovery. The transaction log backups allow you to recover from a media failure and also remove the inactive portion of the transaction log so that it does not need to grow. Bulk-Logged Recovery The bulk-logged recovery model is similar to full recovery but it differs in the way that bulk operations are captured in the transaction log. With full recovery mode SQL Server writes every row to the transaction log that is inserted with BCP or BULK INSERT. Bulk-logged recovery keeps track of the extents that have been modified by a bulk load operation but does not write each row to the transaction log. This reduces the overall size of the transaction log during bulk load operations and still allows the database to recover after a bulk load operation has occurred. The biggest downside to setting a database to bulk-logged recovery is that the log backups for the databases can be large. The log backups are large because SQL Server copies all the data extents that have been affected by bulk load operations since the last backup of the transaction log. Remember that data extents consist of eight data pages each and each page is 8KB in size. This may not seem like much by today s standards but it can be significant when you re bulk loading a large table. For example consider a table occupying 1GB of space that is truncated each week and reloaded with a bulk insert. The bulk insert operation goes .

TỪ KHÓA LIÊN QUAN
TAILIEUCHUNG - Chia sẻ tài liệu không giới hạn
Địa chỉ : 444 Hoang Hoa Tham, Hanoi, Viet Nam
Website : tailieuchung.com
Email : tailieuchung20@gmail.com
Tailieuchung.com là thư viện tài liệu trực tuyến, nơi chia sẽ trao đổi hàng triệu tài liệu như luận văn đồ án, sách, giáo trình, đề thi.
Chúng tôi không chịu trách nhiệm liên quan đến các vấn đề bản quyền nội dung tài liệu được thành viên tự nguyện đăng tải lên, nếu phát hiện thấy tài liệu xấu hoặc tài liệu có bản quyền xin hãy email cho chúng tôi.
Đã phát hiện trình chặn quảng cáo AdBlock
Trang web này phụ thuộc vào doanh thu từ số lần hiển thị quảng cáo để tồn tại. Vui lòng tắt trình chặn quảng cáo của bạn hoặc tạm dừng tính năng chặn quảng cáo cho trang web này.