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copied!<p>i guess that it is one of the drawbacks of using a ManyToMany relation when you need to update the join table.</p> <p>I would advise creating an entity out of the join table, and then you would only had to create the join entity and save it :</p> <pre><code>public class ProductListItem { @ManyToOne(...) private Product product; @ManyToOne(...) private ProductList productList; ... } </code></pre> <p>And you could still have a transient getter than would return a product list from a product :</p> <pre><code>public class Product { @OneToMany(...) private Set<ProductListItem> items; @Transient public Set<ProductList> getProductLists() { Set<ProductList> list = new LinkedHashSet<ProductList>(); for(ProductListItem item : items) { list.add(item.getProductList()); } return Collections.unmodifiableSet(list); } ... } </code></pre> <p>Same thing for the other side of the manytomany relation.</p> <p>Then, your save operation is just a matter of creating a ProductListItem and saving it, which will load nothing, and need only one insert.</p> <p>Be careful with your already existing hql queries : if they used the link Product<->ProductList, they won't work anymore.</p> <p>if you wish to keep the ManyToMany relation, you should look at : <a href="http://josephmarques.wordpress.com/2010/02/22/many-to-many-revisited/" rel="nofollow noreferrer">http://josephmarques.wordpress.com/2010/02/22/many-to-many-revisited/</a> (i've never tried this solution)</p>

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