Re: Cayenne vs EOF functionality

From: Andrus Adamchik (andru..bjectstyle.org)
Date: Wed Apr 27 2005 - 18:24:48 EDT

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    > Are there any plans to implement the aggregate..YZ
    > functions that EOF has: eg)
    > objectArray.valueForKeyPath(..um.fileSize");

    You may look at it two ways:

    1. To- many relationship is just a simple Java List, so you can create any
    operations working with list data in a general fashion without any
    dependency on Cayenne (i.e. this feature is nice but doesn't belong here).

    or ...

    2. To-many relationship is a "smart" List backed by a database data.
    Performing aggregate operations may be more efficient via a special DB
    query that does not have to read all objects in memory first ... Even
    better - it can be smart about it - if relationship is already faulted, it
    can evaluate an operation in-memory, if not - do a DB query.

    In fact (2) is an extension of (1) and I was thinking about adding this to
    Cayenne. The question is when...

    Andrus



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