Devices are operating system files used to store databases, transaction logs, and their backups. Before you can create a new database, you must create the device(s) the database will be stored on. One device can store many databases, and a database can be stored across more than one device. This chapter tells you how to create and manage devices.
There are two types of devices: database devices and dump devices. Database devices store databases and transaction logs; dump devices store database and transaction log backups. Database devices are stored on disk files. Dump devices can be stored on disks, diskettes, or tapes (or for integration with other applications, named pipes). Only the system administrator (SA) can create devices.
When you install SQL Server, these devices are created:
This device is used by the master, model, tempdb, and pubs databases.
The MSDBDATA device is used by the msdb (scheduling) database, and the MSDBLOG device is used by its transaction log.
DISKDUMP, DISKETTEDUMPA, and DISKETTEDUMPB.
Note Diskette dump devices are supported in order to provide compatibility with earlier releases.
As administrator, you will need to create database devices to support databases and transaction logs, and dump devices to support backup of those databases and transaction logs.
Because creating and dropping devices makes changes to the master database, you should always dump the master database after you add or modify devices.
For more information, choose one of the following topics: