Re: Strange Cayenne problem

From: Andrus Adamchik (andru..bjectstyle.org)
Date: Sat Jun 19 2010 - 14:48:19 UTC

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    This is odd since your query is not even using caching, so it hits the
    DB and returns the data from there. Do you have Cayenne SQL logging
    enabled and does the generated query look like what you expected?

    Andrus

    On Jun 18, 2010, at 11:15 PM, Lucas Holt wrote:

    > Earlier today, I was writing some unit tests and stumbled onto a
    > strange problem with some existing code we have. A result is
    > getting returned for something that does not exist in the database.
    >
    > I've included the method that's getting called below. Given a
    > specific input, we get a valid object even though there is nothing
    > close to it.
    >
    > We have a system with a "publications" table and a publication
    > editions table. The latter is an instance of a publication
    > typically used when we have a newsletter from a specific date. If
    > we use today's date and a publication name we'll call A, we get a
    > PublicationEditions object for publication B on a different date
    > from last year. The primary key is different as is all the other
    > meta data for the PublicationEditions object (a cayenne generated
    > class).
    >
    > The only possibility I've come up with is that there is some hash
    > used in the system and we happened to hit a collision. Is this a
    > possibility? We've been using Cayenne's LRU algorithm, but I've
    > tried switching to oscache today as well with the same results (also
    > LRU).
    >
    > Lucas Holt
    >
    >
    > public com.prime.pcd.db.PublicationEditions lookup(final String
    > publicationName, final Date date)
    > throws IllegalArgumentException, ModelException {
    > com.prime.pcd.db.PublicationEditions pe = null;
    >
    > if (publicationName == null || publicationName.length() > 255
    > || publicationName.length() < 1) {
    > throw new IllegalArgumentException("Invalid publication
    > name");
    > }
    >
    > if (date == null) {
    > throw new IllegalArgumentException("Invalid date");
    > }
    >
    > try {
    > Expression qualifier =
    >
    > Expression
    > .fromString("publicationEditionsPublication.publicationName = $pn
    > and publicationEditionDate=$date");
    > final HashMap<String, Object> map = new HashMap<String,
    > Object>(2);
    > map.put("pn", publicationName);
    > map.put("date", date);
    > qualifier = qualifier.expWithParameters(map);
    > final SelectQuery query = new
    > SelectQuery(com.prime.pcd.db.PublicationEditions.class, qualifier);
    >
    > final List<com.prime.pcd.db.PublicationEditions> editions
    > = dataContext.performQuery(query);
    > logger.debug( "Number of found items is " +
    > editions.size());
    > if (!editions.isEmpty()) {
    > pe = editions.get(0);
    > logger.debug(pe.getPublicationEditionsId() + ", " +
    > pe.getPublicationEditionsPublication().getPublicationName());
    > }
    > } catch (CayenneRuntimeException ce) {
    > logger.error("Cayenne error looking up edition: " +
    > ce.getMessage());
    > throw new ModelException("Could not lookup edition");
    > }
    >
    > return pe;
    > }
    >
    >



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