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sqlsql-servert-sqlisolation-leveltransaction-isolation

How to Select UNCOMMITTED rows only in SQL Server?

I am working on DW project where I need to query live CRM system. The standard isolation level negatively influences performance. I am tempted to use no lock/transaction isolation level read uncommitted. I want to know how many of selected rows are identified by dirty read.

Solution

  • Maybe you can do this:

    SELECT * FROM T WITH (SNAPSHOT)
EXCEPT
SELECT * FROM T WITH (READCOMMITTED, READPAST)

    But this is inherently racy.