title: JPA: @ElementCollection and InheritanceType.TABLE_PER_CLASS -> Duplicate column name
body: <p>I've created the following scenario:</p>
  
  <pre><code>@javax.persistence.Entity
  @Inheritance(strategy = InheritanceType.TABLE_PER_CLASS)
  public class MyEntity implements Serializable{
      @Id
      @GeneratedValue
      protected Long id;
      ...
      @ElementCollection
      @CollectionTable(name="ENTITY_PARAMS")
      @MapKeyColumn (name = "ENTITY_KEY")
      @Column(name = "ENTITY_VALUE")
      protected Map&lt;String, String&gt; parameters;
      ...
  }
  </code></pre>
  
  <p>As well as:</p>
  
  <pre><code>@javax.persistence.Entity
  public class Sensor extends MyEntity{
      @Id
      @GeneratedValue
      protected Long id;
      ...
  
      // so here "protected Map&lt;String, String&gt; parameters;" is inherited !!!!
      ...
  }
  </code></pre>
  
  <p>So running this example, no tables are created and i get the following message:</p>
  
  <pre><code>WARNUNG: Got SQLException executing statement "CREATE TABLE ENTITY_PARAMS (Entity_ID BIGINT NOT NULL, ENTITY_VALUE VARCHAR(255), ENTITY_KEY VARCHAR(255), Sensor_ID BIGINT NOT NULL, ENTITY_VALUE VARCHAR(255))": com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Duplicate column name 'ENTITY_VALUE'
  </code></pre>
  
  <p>I also tried overriding the attributes on the Sensor class...</p>
  
  <pre><code>@AttributeOverrides({
      @AttributeOverride(name = "ENTITY_KEY", column = @Column(name = "SENSOR_KEY")),
      @AttributeOverride(name = "ENTITY_VALUE", column = @Column(name = "SENSOR_VALUE"))
  })
  </code></pre>
  
  <p>... but the same error.</p>
  
  <p><strong>EDIT:</strong></p>
  
  <p>Okay, I'd found out that with the Inheritance strategy "JOINED" as well as with "SINGLE_TABLE" everything works fine.
  Also it seems that it has nothing to do with the EclipseLink version - I tried 1.3 and 2.0.1.</p>
  
  <p><strong>END_EDIT</strong></p>
  
  <p>Can anybody help me?</p>