NEC Storage ReplicationControl SQL Option, User Manual

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Chapter 3 Database System Configuration
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Chapter 3 Database System Configuration
Database configuration and concept of backups for the Microsoft SQL Server 2000 are briefly described below.
For details, refer to the Microsoft SQL Server 2000 Books Online.
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The Microsoft SQL Server 2000 database consists of three files; the primary data file, the secondary
data file and the log file. The primary data file and the secondary data file are also simply called “data
file”.
Figure 3-1 Database Configuration
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Primary data file
One database always has one primary data file. As the starting point of the database, the primary
data file points to the locations of the secondary data and log files (File1.mdf in the diagram above).
The file name extension for the primary data file is .mdf.
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Secondary data file
As a data file, the secondary data file sometimes does not exist and sometimes multiple secondary
data files exist (File2.ndf, File3.ndf and File4.ndf).
The extension for the secondary data file is normally .ndf.
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Log file
Refers to the file where the log for recovery is stored. At least one file is required; sometimes, two or
more files also exist (File1.ldf and File2.ldf in the diagram above).
The file name extension for the log file is normally .ldf.
File group 1 File group 2
File1.mdf
File2.ndf
File3.ndf
File4.ndf File1.ldf File2.ldf
Data file
Log file
Database