Snapshot isolation must be enabled by setting the "ALLOW_SNAPSHOT_ISOLATION ON" database option before it is used in transactions. You
You must enable snapshot isolation in each database that uses it with the Transact-SQL ALTER DATABASE statement.
In this respectcase, snapshot isolation differs from the traditional isolation levels of READ COMMITTED, REPEATABLE READ, SERIALIZABLESERIALIZED, and READ UNCOMMITTED, which require no configuration.
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To check what the current snapshot isolation level is, run the following SQL:
If the query returns 0 then it is turned off.
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For avoiding lock in parallel sessions, table have to be created with ALLOW_PAGE_LOCKS = OFF option. |