Home Forums Article Discussions Article Discussions by Author Discuss content posted by Wayne Sheffield Transaction Isolation Levels RE: Transaction Isolation Levels

  • February 14, 2014 at 10:14 am

    #1689138

    jemerson 16199 (2/13/2014)

    As you point out Read Committed Snapshot provides a transactionally consistent set of data at the time the Statement began. Therefore, if T1 reads a row; T2 later commits changes to that row; and T1 reads that row again it will get a different result on the second read. So, Repeatable Read is not guaranteed by Read Committed Snapshot.

    Thanks for reading the article and responding!

    If we take a closer look at the snapshot example in the article, "T1" is reading the same set of rows twice, and during that time "T2" is adding a row. Since "T1" is doing both reads in a transaction, both of the reads are returning the same data, without the modifications that "T2" is making.

    Wayne
    Microsoft Certified Master: SQL Server 2008
    Author - SQL Server T-SQL Recipes

    If you can't explain to another person how the code that you're copying from the internet works, then DON'T USE IT on a production system! After all, you will be the one supporting it!
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