SQL Server Database Administrator Question:
What are database files and filegroups?
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Answer:
Database files are used for mapping the database over some operating system files. Data and log information are separate. SQL server database has three types of database files:
Primary: starting point of a database. It also points to other files in database. Extension: .mdf
Secondary: All data files except primary data file is a part of secondary files. Extension: .ndf
Log files: All log information used to recover database. Extension: .ldf
Primary: starting point of a database. It also points to other files in database. Extension: .mdf
Secondary: All data files except primary data file is a part of secondary files. Extension: .ndf
Log files: All log information used to recover database. Extension: .ldf