Michael T2 (12/12/2012)
Is that not good to use nolocks? I use them alot on queries that i do not need total accuracy.
Actually NOLOCK is far worse than simply dirty reads. You can get duplicate or even missing data. It can cause bugs that are impossible to reproduce and happen sporadically.
Here are a few articles that explain this hint in detail.
http://sqlblog.com/blogs/andrew_kelly/archive/2009/04/10/how-dirty-are-your-reads.aspx
http://blogs.msdn.com/b/davidlean/archive/2009/04/06/sql-server-nolock-hint-other-poor-ideas.aspx
http://www.jasonstrate.com/2012/06/the-side-effect-of-nolock/[/url]
Now I am not saying that there is not a use for this but it is very important that you understand exactly what it is doing. Often times using an isolation level (snapshot isolation) is preferred because you don't have the consistency issues that you do with NOLOCK.
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