SoberCounsel (12/18/2012)
I knew by suggesting it that a few eyebrows would probably be raised!Thanks Sean, for adding the links to further info about the nolock hint... as it happens, I was already aware of the issues it can cause (not just dirty reads!), and so I feel I have to highlight that I wasn't suggesting to just chuck it into queries regardless!!
I do still find that it's a useful hint - for me, it comes in most useful when dealing with large OLTP tables - though familiarity with the actual data being queried is a must, as is awareness of the potential problems with the hint.
😉
You might want to take a look at isolation for large OLTP situations. Frequently using snapshot isolation is a better approach than using NOLOCK. It does have a little bit of associated overhead too. Nothing comes free in the database universe. 😛
http://msdn.microsoft.com/en-us/library/ms173763%28v=sql.105%29.aspx
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