Re: Prefetching has no effect

From: Andreas Hartmann (andrea..pache.org)
Date: Mon Sep 28 2009 - 04:41:34 EDT

  • Next message: Borut Bolčina: "SQLTemplate with SQL MAX function"

    Andreas Hartmann schrieb:
    > Andreas Hartmann schrieb:
    >> I'm trying to get a large set of objects using prefetching.
    >
    > […]
    >
    >> To me this looks like everything should be available after this query.
    >> Nevertheless, Cayenne issues additional queries when I access the
    >> RecipientField and Recipient properties:
    >
    > Now that's interesting.
    >
    > If the table contains 22.000 records, the additional queries are executed.
    >
    > If it contains only 100 records, the additional queries are not
    > executed, i.e. prefetching works as expected.
    >
    > Is there some mechanism to limit the size of the object structure built
    > using a single query, maybe due to memory issues?

    A fellow developer just pointed out that the garbage collector has
    probably started to remove the objects that were created based on the
    first big query, so that additional queries are launched to re-create them.

    For the moment I'm using an SQLTemplate returning data records.

    -- Andreas

    -- 
    Andreas Hartmann, CTO
    BeCompany GmbH
    http://www.becompany.ch
    Tel.: +41 (0) 43 818 57 01
    



    This archive was generated by hypermail 2.0.0 : Mon Sep 28 2009 - 04:42:06 EDT