Using NOLOCK Hint in EF4?

sql-server linq entity-framework isolation-level nolock
John picture John · Jan 26, 2010 · Viewed 10.9k times · Source

We're evaluating EF4 and my DBA says we must use the NOLOCK hint in all our SELECT statements. So I'm looking into how to make this happen when using EF4.

I've read the different ideas on how to make this happen in EF4, but all seem like a work around and not sanctioned by Microsoft or EF4. What is the "official Microsoft" response to someone who wants their SELECT statement(s) to include the NOLOCK hint when using LINQ-to-SQL / LINQ-to-Entities and EF4?

By the way, the absolute best information I have found was right here and I encourage everyone interested in this topic to read this thread.

Thanks.

Answer

gbn picture gbn · Jan 26, 2010

NOLOCK = "READ UNCOMMITTED" = dirty reads

I'd assume MS knows why they chose the default isolation level as "READ COMMITTED"

NOLOCK, in fact any hint, should be used very judiciously: not by default.

Your DBA is a muppet. See this (SO): What can happen as a result of using (nolock) on every SELECT in SQL Sever?. If you happen to work at a bank, or any institution where I may have an account please let me know so I can close it.

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