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POhibernate how to select the many-side from an one-to-many relation
 

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    <p>everyone. I'm brand new using Hibernate. </p> <p>So here I face a question, I have an entity like below:</p> <pre><code>&lt;class name="cn.edu.scau.librarica.dao.MessageSession" table="msg_session"&gt; &lt;id name="msid" type="long" unsaved-value="null"&gt; &lt;generator class="identity"/&gt; &lt;/id&gt; &lt;list name="msgs" cascade="all"&gt; &lt;key column="msid" update="false" unique="true" not-null="true"/&gt; &lt;list-index column="list_index"/&gt; &lt;one-to-many class="Message" /&gt; &lt;/list&gt; &lt;/class&gt; </code></pre> <p>And now what I want to achieve is:</p> <pre><code> select Message m where msid=# and m.t&lt;## and m.t&gt;### </code></pre> <p>How can I represent it with Criteria?<br> Thank you for your attentions and advices, in advance.</p> <hr> <p><strong>UPDATE</strong><br> As one of the answer guide, I have got the point that composite-element is not queryable, so I made a both-sid one-to-many map(changed are above) And now I can query but now I found another problem:<br> <strong>How can I mapped the composite-id with foreign-key</strong><br> <code>Message</code> are map like this:</p> <pre><code>&lt;class name="Message"&gt; &lt;composite-id&gt; &lt;generator class="foreign"&gt; &lt;!-- What here??? --&gt; &lt;/generator&gt; &lt;/composite-id&gt; &lt;/class&gt; </code></pre> <p>As instructed, one-to-many may use <code>set</code> rather than <code>list</code>, so I can hardly find sample meets my need(due to Message should be ordered).<br> Any advice? I am still searching for that. Thanks for help.</p>
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    1. COYou need to map Message class similar like how you mapped MessageSession and write criteria query as explained on hibernate's manual
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    2. COYou need to say <generator class="assigned"> and leave it empty. That means hibernate will not automatically generate ids when you create new instances of message - you will have to do it in your program.
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    3. CO<generator class="foreign"/> doesn't mean what you think it means :-). Take my earlier advise - spend some time reading up about hibernate.
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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