Hi guys, I'm working on OGM-236 which consists to use by default the IN_ENTITY mode for association storage strategy instead of COLLECTION. I've just found out a little issue, when we use @JoinColumns over a @OneToMany property to map an @EmbeddedID with the IN_ENTITY mode, the navigation information are not stored directly into the document itself but another document composed by the join columns as the _id and the navigation information (in that case the IDs that the entity is related to).
Concretely, let's starting from this mapping: https://github.com/hibernate/hibernate-ogm/blob/master/hibernate-ogm-core/src/test/java/org/hibernate/ogm/test/id/Label.java https://github.com/hibernate/hibernate-ogm/blob/master/hibernate-ogm-core/src/test/java/org/hibernate/ogm/test/id/News.java https://github.com/hibernate/hibernate-ogm/blob/master/hibernate-ogm-core/src/test/java/org/hibernate/ogm/test/id/NewsID.java and run this test with the IN_ENTITY mode on (to make the switch, a modification into MongoDBDatastoreProvider.configure() is needed) https://github.com/hibernate/hibernate-ogm/blob/master/hibernate-ogm-core/src/test/java/org/hibernate/ogm/test/id/CompositeIdTest.java We can expect to have something like: { "_id": { "author": "Guillaume", "title": "There are more than 20 JUGs in France" }, "content": "Great! Congratulations folks", "labels": [ { "id": NumberLong(5) } ] } It means this News is related to 1 Label of which ID is 5. But due to @JoinColumns we got this (both documents are from the News collection): { "_id": { "author": "Guillaume", "title": "There are more than 20 JUGs in France" }, "content": "Great! Congratulations folks", "labels": [] } { "_id": { "news_author_fk": "Guillaume", "news_topic_fk": "There are more than 20 JUGs in France" }, "labels": [{ "id": NumberLong(5) }] } Of course at the loading, when the News seems not related to any Label because the "labels" field is empty. A workaround it to change the @JoinColumns from: @JoinColumns({@JoinColumn(name="news_topic_fk", referencedColumnName = "newsid.title", nullable = false) , @JoinColumn(name="news_author_fk", referencedColumnName = "newsid.author", nullable = false)}) private List<Label> labels; @JoinColumns({@JoinColumn(name="title", referencedColumnName = "newsid.title", nullable = false) , @JoinColumn(name="author", referencedColumnName = "newsid.author", nullable = false)}) private List<Label> labels; Note that the new value of each @JoinColumn's name is the same as referenced property from the @Embedded entity. I see there are 2 fix possible for this issue: - we can say in case of IN_ENTITY mode don't use @JoinColumns' name to store the navigation property but the property from the referenced column. - at the loading, we can check also the documents created due to @JoinColumns Personally, I would tend to the first approach which is more natural in terms of storage and more readable. What do you think ? Let me know if you need more information. Guillaume _______________________________________________ hibernate-dev mailing list hibernate-dev@lists.jboss.org https://lists.jboss.org/mailman/listinfo/hibernate-dev
