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POHibernate -- Using @SecondaryTable, @OneToMany
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copied!<p>(Simplified Example below)</p> <p>I'm trying to map one POJO class with 2 DB tables and also creating a OneToMany association. Here is how the class looks like..</p> <pre><code>@Entity @Table(name = "external_data") @SecondaryTable(name = "external_data_hierarchy") public class ExternalData { private int externalDataId; @OneToMany(fetch = FetchType.LAZY) @JoinTable(name = "external_data_hierarchy") @JoinColumn(name = "external_data_parent_id") private List<ExternalData> children; .. } </code></pre> <p>Here are the tables..</p> <pre><code>mysql> desc external_data; +------------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +------------------+--------------+------+-----+---------+----------------+ | external_data_id | int(11) | NO | PRI | NULL | auto_increment | +------------------+--------------+------+-----+---------+----------------+ 5 rows in set (0.06 sec) mysql> desc external_data_hierarchy; +----------------------------+---------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------------------------+---------+------+-----+---------+----------------+ | external_data_hierarchy_id | int(11) | NO | PRI | NULL | auto_increment | | external_data_parent_id | int(11) | YES | MUL | NULL | | | external_data_child_id | int(11) | YES | MUL | NULL | | +----------------------------+---------+------+-----+---------+----------------+ 3 rows in set (0.00 sec) Note: "external_data_parent_id" and "external_data_child_id" columns refer external_data.external_data_id column. </code></pre> <p>As you can tell, I'm trying to store parent-child relationship in a different table. Now, when I try create() on ExternalData without setting the children, it works. When I try to fetch this created data using ExternalData.getChildren() I get the following exception..</p> <pre><code>[main] WARN in [org.hibernate.util.JDBCExceptionReporter.logExceptions(JDBCExceptionReporter.java:100)] - SQL Error: 1054, SQLState: 42S22 [main] ERROR in [org.hibernate.util.JDBCExceptionReporter.logExceptions(JDBCExceptionReporter.java:101)] - Unknown column 'externalda0_1_.external_data_id' in 'on clause' </code></pre> <p>What am I doing wrong?</p>

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