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    <p>As said</p> <blockquote> <p>When i try deleting the UserProfile entity, the corresponding User entity still stays</p> </blockquote> <p>Maybe when you try to remove a UserProfile you get an integrity constraint violation from the database - do you use MyISAM engine in MySQL ?</p> <p>But as you does not says nothing about it. Maybe your UserProfile entity does not have a reference to a User entity. </p> <p>As said in JPA specification</p> <blockquote> <p>remove operation <strong>is cascaded to entities referenced by X</strong>, if the relationship from X to these other entities is annotated with the cascade=REMOVE or cascade=ALL annotation element value</p> </blockquote> <p>Something like</p> <pre><code>UserProfile up = entityManager.find(UserProfile.class, id); entityManager.close(); // Notice User is null outside a persistence context // So user will be not removed from the database because UserProfile does not have a reference to it up.setUser(null); entityManager.getTransaction().begin(); entityManager.remove(up); entityManager.getTransaction().commit(); </code></pre> <p>Or you have something like</p> <pre><code>entityManager.getTransaction().begin(); UserProfile up = entityManager.find(UserProfile.class, id); // throws UPDATE USER_PROFILE SET USER_ID = NULL up.setUser(null); // up.getUser() is null // So user is not removed entityManager.remove(up); entityManager.getTransaction().commit(); </code></pre> <p>In response to ChhsPly's comment:</p> <p>In Java Persistence with Hibernate book, you see the following</p> <blockquote> <p>The cascade attribute is directional: <strong>It applies to only one end of the association</strong>. </p> </blockquote> <p>I think it would be better as</p> <blockquote> <p>It applies to only one end of the association <em>per operation</em></p> </blockquote> <p>So you can put cascade attribute in both sides at the same time, even in a bidirectional relationship. So ChssPly is right.</p> <p>mappdeBy attribute <strong>sets up the bidirectional relationship</strong>. mappedBy attribute designated the Address entity as the inverse side of the relationship. This means that the Customer entity is the owning side of the relationship.</p> <p>ChssPly is right when he says <em>mappedBy has nothing to do with cascading</em></p>
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    1. POA question on JPA Cascading
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    1. COThat is incorrect. First of all, `mappedBy` has nothing to do with cascading - it's used to signify the non-owner side of bi-directional relationship. Secondly, "cascade" attribute is an **attribute** (as in "not an association") so it's not unidirectional or bi-directional in itself. It can be applied to either uni-directional or bi-directional association (including both sides simultaneously). Certain cascade **types** may not make sense on non-owner association side.
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    2. COThank you, ChssPly. As i am a non-native english speaker, i have some limitations when writing some answer. Added to original answer.
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    3. CO@Arthur - thanks for your edits (upvoting); I didn't mean to be harsh or nitpick at phrasing - just wanted to clarify some points. English isn't my first language either :-)
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