How to dynamically order many-to-many relationship with JPA or HQl?

Posted by Indrek on Stack Overflow See other posts from Stack Overflow or by Indrek
Published on 2010-06-08T23:37:55Z Indexed on 2010/06/08 23:52 UTC
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Filed under:

jpa

|

many-to-many

|

hql

|

order-by

|

play-framework

I have a mapping like this:

@ManyToMany(cascade = CascadeType.PERSIST)
    @JoinTable(
            name="product_product_catalog",
            joinColumns={@JoinColumn(name="product_catalog", referencedColumnName="product_catalog")},
            inverseJoinColumns={@JoinColumn(name="product", referencedColumnName="product")})
    public List<Product> products = new ArrayList<Product>();

I can fetch the products for the catalog nicely, but I can't (dynamically) order the products. How could I order them? I probably have to write a many-to-many HQL query with the order-by clause? I though of passing the orderBy field name string to the query, or is there a better solution?

Tables are: products, product_catalog, product_product_catalog (associative table)

P.S. Using Play! Framework JPASupport for my entities.

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