Help setting Transaction Isolation level

  • I am trying to test setting Transaction Isolation levels on our dev server which is sql7.

    I have an open QA page with this code

    SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED

    GO

    begin tran

    update tblWorksOrder set strClientOrderNumber = '0000'

    where uGuid='{CD007F93-8C41-4CCB-B421-9C46CF9ADE1F}'

    which I presumed from the articles ive read would mean that if another user tried to do a select on that same record before it was commited would return strClientOrderNumber of '0000' not the original which was '9999'. But when I go to my dev website and try and open the page that displays that record it just freezes and does not display until i run

    commit tran

    Am I totally missing something.

    I gathered that if I had set it to READ COMMITTED my web page would only display '0000' once the transaction had been commited.

    Whatever I do the page that tries to access that record is locked out from retrieving any data until I commit the transaction.

    Can someone explain what is happening and be able to give me a working example of demonstrating the different Isolation levels in practise.

    Thanks in advance.

  • Your understanding is partially correct, the only thing that you are missing is:-

    You need to set the isolation level on the connection that is reading the data (your website), not on the one that is doing the updating (your QA session).

Viewing 2 posts - 1 through 1 (of 1 total)

You must be logged in to reply to this topic. Login to reply