Re: query_governor_cost_limit setting not working with cayenne?

From: Andrus Adamchik (andru..bjectstyle.org)
Date: Sun Dec 21 2008 - 09:34:09 EST

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    On Dec 21, 2008, at 4:16 PM, KathyS wrote:

    > Related question, if you have time. How can I hook onto connection
    > creation
    > in the pool? I'd love to be able to run the "set ..cost" statement
    > for each
    > new connection.

    This is also fairly straightforward. Cayenne uses a
    javax.sql.DataSource object to obtain connections. In many cases
    DataSource is provided by the environment (e.g. webapp containers or
    appservers) [1], so you can check the docs of you container on how to
    install a custom DataSource there.

    In cases when Cayenne manages its own DataSource (i.e. if you selected
    "org.apache.cayenne.conf.DriverDataSourceFactory" for the DataNode
    "DataSource Factory" in the Modeler), you can supply your own
    DataSourceFactory (also via the Modeler).

    FWIW, I won't be surprised if SQLServer JDBC driver would support
    passing something in the URL that would set the "cost".

    Andrus

    [1] http://cayenne.apache.org/doc/using-jndi.html

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