[ANN] Cayenne 1.2 Milestone 1 with SQLServer/MySQL identity columns support

From: Andrus Adamchik (andru..bjectstyle.org)
Date: Sun Nov 21 2004 - 23:42:28 EST

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    Hi,

    The first 1.2 milestone was released tonight. Download it from

    http://objectstyle.org/cayenne/

    It includes a few smaller things not available in 1.1, but the most
    important one is CAY-243
    (http://objectstyle.org/jira/secure/ViewIssue.jspa?key=CAY-243). I
    promised for some time to provide support for auto-incrementing columns
    (aka "identity" columns on SQLServer). M1 is the first major step in
    this direction. It includes modeler support for "auto" DbAttributes and
    allows Cayenne current PK generator to coexist with DB schemas that
    have identity columns. What that means is that:

    * DbAttributes can be configured in the Modeler as "auto"
    * On SQLServer and MySQL Modeler can be used to create tables with
    "auto" columns (on other DBs this is simply ignored).
    * Cayenne PK generator can be used to populate auto columns [in the
    past SQLServer would throw an exception if you do that, but I found a
    SQLServer-specific workaround; MySQL worked fine in the past].

    What's not there yet:

    * Cayenne still doesn't take advantage of auto columns for real, rather
    it "coexists" with them. I am working on full support, but since there
    are people who need to use Cayenne with existing schemas *right now*, I
    figured I'd release what I have. IMO M1 provides a reasonable
    transparent workaround, so once full auto columns support is done,
    there hopefully will be no "migration" needed, just swapping
    cayenne.jar.

    * Modeler can't reverse-engineer "auto" setting for DB attributes
    (though it can generate it when creating DB schema). AFAIK there is no
    support for that in JDBC API. Though there is probably a db-specific
    way to achieve that. If anyone has working ideas, let me know.

    Thanks
    Andrus



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