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POJPA OneToMany eager fetch does not work
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  1. POJPA OneToMany eager fetch does not work
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    copied!<p>I have a weird problem with two entities with one-to-many relation in JPA. I am using Glassfish 3.1.2.2 with EclipseLink 2.3.2. This is the first entity:</p> <pre><code>@NamedQueries({ @NamedQuery(name="SampleQueryGroup.findAll", query="SELECT g FROM SampleQueryGroup g") }) @Entity public class SampleQueryGroup implements Serializable { // Simple properties, including id (primary key) @OneToMany( mappedBy = "group", fetch = FetchType.EAGER, cascade = {CascadeType.REMOVE, CascadeType.MERGE} ) private List&lt;SampleQuery&gt; sampleQueries; // Gettes/setters, hashcode/equals } </code></pre> <p>And this is the second one:</p> <pre><code>@Entity public class SampleQuery implements Serializable { // Simple properties, including id (primary key) @ManyToOne(cascade = {CascadeType.PERSIST}) private SampleQueryGroup group; // Gettes/setters, hashcode/equals } </code></pre> <p>I have a stateless session bean which uses an injected <code>EntityManager</code> to run <code>SampleQueryGroup.findAll</code> named query. I also have a CDI managed bean which calls the SSB method and iterates through <code>SampleQueryGroup.getSampleQueries()</code> for each <code>SampleQueryGroup</code> returned by the method. I didn't paste the code as it is pretty straightforward and somehow standard for any Java EE application.</p> <p>The problem is the eager fetch does not work and <code>getSampleQueries()</code> returns an empty list. However, when I change the fetch type back to FetchType.LAZY, everything works and I get the list correctly populated. I don't understand why this happens. Does it have anything to do with internal caching mechanisms?</p>
 

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