Re: Application logic and Business logic

From: frebe (fredrik_bertilsson_at_passagen.se)
Date: 03/14/05

  • Next message: frebe: "Re: Application logic and Business logic" 
    Date: 13 Mar 2005 22:11:42 -0800

    > However, an RDB is not the only data management system that
    > can do that.

    Do you have any references the the othe "data management systems" that
    can do that?

    > One is DML, which was the query language for
    > ObjectStore several years ago. Another is the elusive OQL.

    OQL is heavily based on relational calculus. A databases that supports
    OQL is an relational database extended with some OO features (which I
    think is a good idea). A network database would never be able to
    support OQL.

    ObjectStore DML seem to share the same basic idea with JDOQL. These
    query languages is also an extention of the relational model.

    The only real difference between SQL and your OO query languages is
    that in SQL you say "table" and "record" instead of "class" and
    "object". If you pretend that "table"=="class" and "record"=="object",
    you will discover that they are identical.

    How can you accept OQL query string spread around your application,
    when you can't accept SQL? As a matter of fact, mostly it is hard so
    see the difference between a OQL and SQL query.

    Fredrik Bertilsson
    http://butler.sourceforge.net

  • Next message: frebe: "Re: Application logic and Business logic"

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    • Re: Application logic and Business logic
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