DBCC UPDATEUSAGE (0); GO Best practice to use DBCC UPDATEUSAGE i ntermittently and must if you have upgraded the database from SQL 2000 to 2005. The usual working fashion of this DBCC statement is to correct the rows, used pages, reserved pages, leaf pages, and data page counts for each partition in a table or index. If there are no inaccuracies in the system tables, DBCC UPDATEUSAGE returns no data. If inaccuracies are found and corrected and you have not used WITH NO_INFOMSGS, DBCC UPDATEUSAGE...(
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Read the complete post at http://sqlserver-qa.net/blogs/tools/archive/2007/08/13/how-to-get-updated-page-or-row-count-information-for-the-current-database.aspx