Have you ever expected an index seek or clustered index seek for a query, where SQL Server turned its back and decided to use scan?
Do you believe in this statement: "Scan reads through the object (table/index) from top to bottom looking for the records that it needs while seek goes directly to the part of the object that it needs and reads to where the data that it needs ends. This is obviously a must more efficient operation than a scan, as database server already knows where the data is that it is looking for"
If your answer is true for any of the questions, you need to read my article.
http://www.sql-server-performance.com/articles/dba/understanding_scans_seeks_p1.aspx
As the above site does not allow reader feedback, I am opening this area for your comments
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