Need to migrate from oracle to sql server

  • HI All,

    We have requirement to migrate a database from oracle to sql server 2008 .

    What is best method to do the migration?

    We are Planing to use SSMA tool for migration.

    Can any one tell me what are basic pre-requests and steps to follow?

    THanks in advance............

  • bala2 (9/27/2013)


    HI All,

    We have requirement to migrate a database from oracle to sql server 2008 .

    What is best method to do the migration?

    We are Planing to use SSMA tool for migration.

    Can any one tell me what are basic pre-requests and steps to follow?

    THanks in advance............

    This is not a simple task to say the least. It is far more than just creating some tables and moving data. You need to evaluate the datatypes, you need to look at every single procedure, you need to look at triggers, etc etc etc...

    _______________________________________________________________

    Need help? Help us help you.

    Read the article at http://www.sqlservercentral.com/articles/Best+Practices/61537/ for best practices on asking questions.

    Need to split a string? Try Jeff Modens splitter http://www.sqlservercentral.com/articles/Tally+Table/72993/.

    Cross Tabs and Pivots, Part 1 – Converting Rows to Columns - http://www.sqlservercentral.com/articles/T-SQL/63681/
    Cross Tabs and Pivots, Part 2 - Dynamic Cross Tabs - http://www.sqlservercentral.com/articles/Crosstab/65048/
    Understanding and Using APPLY (Part 1) - http://www.sqlservercentral.com/articles/APPLY/69953/
    Understanding and Using APPLY (Part 2) - http://www.sqlservercentral.com/articles/APPLY/69954/

  • This is probably going to be a very big job. I wouldn't plan on having it done quickly if you're using any real functionality in Oracle other than storing data. It's been years since I've used Oracle, but here are some highlights off the top of my head:

    - The data types don't migrate simply. You're going to have to take Unicode and collation into account when moving data.

    - Oracle has packages, but SQL Server has no such object. These will have to be handled one by one.

    - If you have used any CREATE TYPE x AS OBJECT and have logic in the object body, you're going to have to handle them one by one.

    - In Oracle, cursors are loaded into upper memory and run very quickly. In SQL Server, cursors are notoriously slow.

    - Every one of your FOR x IN loops are going to have to be done manually.

    - Triggers are the same in concept, but not in implementation.

    - Dates are handled very differently. There is no TO_CHAR function in SQL Server.

    I would be absolutely stunned if any migration tool was 100% successful. The odds are that you're going to have to manage the expectations of the "powers that be" while you plod through mountains of functionality. I hope you already know both languages.

    The single biggest piece of advice I can give you is to test, test, test.

  • Like the others said before it can be quite a challenge but it start with the SSMA for Oracle

    http://technet.microsoft.com/en-us/library/hh313179.aspx

    [font="Verdana"]Markus Bohse[/font]

  • MarkusB (9/28/2013)


    Like the others said before it can be quite a challenge but it start with the SSMA for Oracle

    http://technet.microsoft.com/en-us/library/hh313179.aspx

    A very good friend of mine, a successful developer and DBA described the SSMA as "adequate but not enough".

    The architectures of both RDBMSs are hideously different. So different in fact that this friend chose to write the database from scratch, import the data required into each table via a common data format and then build the constraints.

    It turned out to be significantly faster than the migration through code changing.

    But just a quick question: What is the reason for migrating out of Oracle?

Viewing 5 posts - 1 through 4 (of 4 total)

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