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copied!<p>There are a couple of things you can look at to optimize your query performance.</p> <ol> <li><p>Ensure that you just have the minimum of data. Make sure you select only the columns you need. Reduce field sizes to a minimum.</p></li> <li><p>Consider de-normalising your database to reduce joins</p></li> <li><p>Avoid loops (i.e. fetch cursors), stick to set operations.</p></li> <li><p>Implement the query as a stored procedure as this is pre-compiled and will execute faster.</p></li> <li><p>Make sure that you have the correct indexes set up. If your database is used mostly for searching then consider more indexes.</p></li> <li><p>Use the execution plan to see how the processing is done. What you want to avoid is a table scan as this is costly.</p></li> <li><p>Make sure that the Auto Statistics is set to on. SQL needs this to help decide the optimal execution. See Mike Gunderloy's great post for more info. <a href="http://www.developer.com/db/article.php/10920_3622881_1" rel="nofollow noreferrer">Basics of Statistics in SQL Server 2005</a></p></li> <li><p>Make sure your indexes are not fragmented <a href="http://www.mssqlcity.com/Articles/Adm/index_fragmentation.htm" rel="nofollow noreferrer">Reducing SQL Server Index Fragmentation</a></p></li> <li><p>Make sure your tables are not fragmented. <a href="http://www.sql-server-performance.com/articles/per/detect_fragmentation_sql2000_sql2005_p1.aspx" rel="nofollow noreferrer">How to Detect Table Fragmentation in SQL Server 2000 and 2005</a></p></li> </ol>

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