Oracle Isolation Levels

From: fmh <fmhabash_at_gmail.com>
Date: Thu, 20 Feb 2014 10:51:31 -0500
Message-ID: <CADpeV5xReVomVp=kX2pAaojeS1nuLu0ZYh0sUk5HULafmFZUVw_at_mail.gmail.com>

I have been doing some research on this topic & this is what I currently understand ...
1) Oracle allows 3 isolation levels, the default is READ_COMMITTED. 2) This default guarantees data consistency at both statement as well transaction level.
3) The default allows non-repeatable & phantom reads.

My questions are ...
1) The SERIAZABLE isolation level is similar to READ_COMMITTED in that it gurantees cosnstency for the life of the transaction. If this is the case.why is it needed as a separate isolation level option?

2) If the default allows phantom & non-repeatable reads, is this OK? 3) Did you ever have to change Oracle isolation level? If yes, what was your real-life scenario?

Thanks to all.

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Thank you.

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http://www.freelists.org/webpage/oracle-l Received on Thu Feb 20 2014 - 16:51:31 CET