tailieunhanh - Hướng dẫn học Microsoft SQL Server 2008 part 111

Các tập tin dữ liệu trong cơ sở dữ liệu ảnh chụp được các tập tin NTFS thưa thớt. Khi những ảnh chụp cơ sở dữ liệu được tạo ra, các tập tin thưa thớt là trống rỗng và không chứa bất kỳ dữ liệu người dùng. | Part VI Enterprise Data Management 2. Note the logical name of the data files listed under the name column and their sizes. In the preceding example there is only one data file with the logical name AdventureWorks_Data and a size of 200640 KB or 195 MB . 3. For each data file in the source database there is a data file in the database snapshot. The data files in the database snapshot are different from the source database data files. The data files in the database snapshot are NTFS sparse files. When the database snapshot is created the sparse files are empty and do not contain any user data. Because the sparse files can potentially grow up to the size of the data file of the source database at the time the database snapshot was created it is important to verify that the volume where you want to place the database snapshot has enough free space. Even though you can create the database snapshot on a volume with very little space it is recommended that you ensure that the volume has enough free space at least the space of the source database when the database snapshot is created . If the volume runs out of space the database snapshot will be marked suspect and become unusable and will need to be dropped. 4. Execute the following Transact-SQL command to create the database snapshot of the AdventureWorks database CREATE DATABASE AdventureWorks_Snapshot ON NAME AdventureWorks_Data FILENAME J MSSQL DATABASE SNAPSHOTS AdventureWorks AS SNAPSHOT OF AdventureWorks GO The FILENAME appears to wrap in the preceding code. In actual code it should not wrap around or you will get the error shown here Msg 5133 Level 16 State 1 Line 1 Directory lookup for the file J MSSQL DATABASE SNAPSHOTS failed with the operating system error 123 The filename directory name or volume label syntax is incorrect. . Best Practice To make it easier to use the database snapshot think about how you want to name it before you start.