Re: Joint Prefetches

From: Andrus Adamchik (andru..bjectstyle.org)
Date: Mon Mar 14 2005 - 21:40:14 EST

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    This was two unrelated bugs. Just checked in the fix... Will keep on
    testing...

    Andrus

    On Mar 11, 2005, at 6:44 PM, Tore Halset wrote:

    > On Mar 7, 2005, at 6:44, Andrus Adamchik wrote:
    >
    >> Just finished a new feature - joint prefetches in SelectQueries.
    >> Still need to document that, but at the user level it comes down to
    >> "SelectQuery.addJointPrefetch()". What's good about joint prefetches:
    >
    > I have one question regarding joint prefetches:
    >
    > A has a toMany to B and B has a flattened toMany to C
    > A<-->>B<<-->>C
    >
    > SelectQuery q = new SelectQuery(A.class);
    > q.addJointPrefetch("bArray");
    > q.addJointPrefetch("bArray.cArray");
    >
    > Cayenne issue a join query between the tree tables A, B and C.
    >
    > Looping all Bs for a given A works, but looping all Cs for a given B
    > result in lots of queries.
    >
    > Am I doing something wrong? Perhaps I should mix standard prefetch and
    > joint prefetch?
    > A single joint prefetch from B to C works if my query-root is B.
    >
    > Regards,
    > - Tore.
    >
    >



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