I'm a little surprised that you're not recommending running CHECKDB on the database in question. Yes, it's marked as suspect, and yes, you might find a cause in the error log, but then again, you might not. Running a database consistency check will frequently identify the root cause. It might be something recoverable through other means than running repair with data loss, which is a very dangerous thing to do to a production system.
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Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning