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How does SqlConnection manages IsolationLevel?

Posted By:      Posted Date: September 21, 2010    Points: 0   Category :Sql Server
 

This MSDN article states that:

An isolation level has connection-wide scope, and once set for a connection with the SET TRANSACTION ISOLATION LEVEL statement, it remains in effect until the connection is closed or another isolation level is set. When a connection is closed and returned to the pool, the isolation level from the last SET TRANSACTION ISOLATION LEVEL statement is retained. Subsequent connections reusing a pooled connection use the isolation level that was in effect at the time the connection is pooled.

The SqlConnection class has no member that may hold the isolation level. So how does a connection know what isolation level to run in???

The reason I'm asking this is because of the following scenario:

  1. I opened a transaction using TransactionScope in Serializable mode, say "T1".
  2. Opened a connection for T1.
  3. T1 is finished/disposed, connection goes back to connection pool.
  4. Called another query on same connection (after getting it from connection pool) and this query runs in serializable mode!!!

Problem:

  1. How does the pooled


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