When planning a SQL Server database, the design must take into consideration a number of factors, including database files and filegroups, transaction logs, the SQL Server installation and its operating environment, and security. This lesson discusses each of these considerations. To map a database, SQL Server 2000 uses a set of operating system files. This file contains the startup information for the database and is used to store data.
Every database has one primary data file.
These files hold all of the data that does not fit into the primary data file. If the primary file can hold all of the data in the database, databases do not need to have secondary data files. Some databases might be large enough to need multiple secondary data files or to use secondary files on separate disk drives to spread data across multiple disks or to improve database performance. These files hold the log information used to recover the database. There must be at least one log file for each database.