Database Consistency Checker (DBCC) commands can give the DBA valuable insight into what’s going on inside SQL Server system. DBCC commands have powerful documented functions and many undocumented capabilities. Current DBCC commands are most useful for performance and troubleshooting exercises.
To learn about all the DBCC commands use the following script in the query analyzer in Management Studio.
DBCC HELP (‘?’)
To learn about syntax of an individual DBCC command by running the following script in query analyzer.
Find more information on this command on Microsoft’s website: http://msdn.microsoft.com/en-us/library/ms176064.aspx