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POJPA SINGLE_TABLE inheritance from two tables
 

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  1. POJPA SINGLE_TABLE inheritance from two tables
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    <pre><code> &lt;entity class="com.AbstractClass" access="FIELD"&gt; &lt;table name="TABLE_0"/&gt; &lt;secondary-table name="TABLE_1"&gt; &lt;primary-key-join-column name="TABLE0_REF_ID" referenced-column-name="TABLE0_ID"/&gt; &lt;/secondary-table&gt; &lt;inheritance strategy="SINGLE_TABLE"/&gt; &lt;discriminator-column name="TYPE" discriminator-type="INTEGER"/&gt; &lt;attributes&gt; &lt;id name="id"&gt; &lt;column table="TABLE_1" name="TABLE1_ID"/&gt; &lt;generated-value generator="GLOBAL_GENERATOR" strategy="SEQUENCE"/&gt; &lt;/id&gt; &lt;basic name="name"&gt; &lt;column table="TABLE1" name="NAME"/&gt; &lt;/basic&gt; &lt;/attributes&gt; &lt;/entity&gt; &lt;entity class="com.DateClass"&gt; &lt;discriminator-value&gt;2&lt;/discriminator-value&gt; &lt;attributes&gt; &lt;basic name="date"&gt; &lt;column table="TABLE_1" name="DATE"/&gt; &lt;/basic&gt; &lt;/attributes&gt; &lt;/entity&gt; </code></pre> <p>I'm using Eclipselink for JPA mapping. I have two problems:</p> <ol> <li>When I'm using exact mapping as above eclipselink generating wrong query (wrong table for primary table primary key; I think this is because primary key is in secondary table, but I, can't change this - <code>TABLE_0</code> and <code>TABLE_1</code> have different primary keys and I can not change database): <code>[EL Fine]: sql: SELECT t0.NAME t1.TABLE1_ID FROM TABLE_0 t0, TABLE_1 t1 WHERE (t1.TABLE0_REF_ID = t1.TABLE0_ID)</code></li> <li><p>To solve this problem i'v used following <code>DescriptorCustomizer</code> (I can't switch primary and secondary tables, 'cause must be in primary):</p> <pre><code>@Override public void customize(ClassDescriptor descriptor) throws Exception { descriptor.getAdditionalTablePrimaryKeyFields().clear(); descriptor.getMultipleTableForeignKeys().clear(); descriptor.addForeignKeyFieldNameForMultipleTable("TABLE_0.TABLE0_ID", "TABLE_1.TABLE0_REF_ID"); } </code></pre></li> </ol> <p>In that case query generating correctly, but i'v got list of multiple instances of the same object:</p> <pre> public class GenericDAO { ... public List getAll() { CriteriaQuery cq = em.getCriteriaBuilder().createQuery(entityClass); cq.select(cq.from(entityClass)); return em.createQuery(cq).getResultList(); } } new ClassDAO().getAll(); </pre> <p>Output:</p> <pre><code>13485751-Object_1 13485751-Object_1 13485751-Object_1 13485751-Object_1 .... </code></pre>
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    1. USBeryllium
    1. USshtrih
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      1. POJPA SINGLE_TABLE inheritance from two tables
      1. USChris
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    1. COSorry, why can't you map table1 as the primary table in JPA? It doesnt require database changes. Other than that, the issue seems like you defined the primary-key-join-column going in the wrong direction.
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      1. USChris
    2. COFirst of all, I did not switched tables because discriminator-column must be in primary (I didn't notice that it not showing in question), and primary goal was to build orm-mapping without mapping warnings and errors. And actually I already tried this (had added in customizer `descriptor.getInheritancePolicy().getClassIndicatorField().setTableName("TABLE_1");`). And I thought it did not worked for me. But I mistook exception, thrown during runtime, as mapping exception. So now I'm working out this option.
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      1. POJPA SINGLE_TABLE inheritance from two tables
      1. USshtrih
    3. COAnd this is the solution.
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      1. USshtrih
 

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