Isolation level in OBIEE RPD connection pool

Question

Hi !

There are four types of Isolation levels namely Dirty,Committed,Repeated, and Serializable.

We have gone through the help section of OBIEE RPD, however found it difficult to understand.

Can anyone help understand those levels with some example ?

Secondly there is a Default level also. Which one is this amongst the four mentioned above ?

Thirdly does it impact  OBIEE report (in terms of speed) ?

We use SQL Server 2008, and presently it is set to Default in our connection pool. Do you suggest any other value ?

Regards

AM

Syedsalmancs110 · Answer

The isolation level(It's related to database) setting controls the default transaction locking behavior for all statements issued by a connection.

More on same in below product document link under section "Table 7-4 Connection Pool Properties in the General Tab: Common Properties"

https://docs.oracle.com/cd/E28280_01/bi.1111/e10540/conn_pool.htm#BIEMG1274

Yes incorrect setting can cause performance issues, found below note which discusses on Isolation Level w.r.t. SQL Server

https://technet.microsoft.com/en-us/library/ms189122(v=sql.105).aspx