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POHow do I get NHibernate to return data on composite key table?
 

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  1. POHow do I get NHibernate to return data on composite key table?
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    <p>I have a junction table in my database. I need to read the id values and use them in my program. I cannot get NHibernate to return any records in the database. It appears as though my mapping file "compiles", but no results are returned.</p> <p><strong>LinkTable</strong></p> <ul> <li><strong>int</strong> id_ObjectA <em>(foreign key)</em></li> <li><strong>int</strong> id_ObjectB <em>(foreign key)</em></li> </ul> <p><strong>LinkDAO Class:</strong></p> <pre><code>public class LinkDAO { public virtual ObjectADAO ObjectA { get; set; } public virtual ObjectBDAO ObjectB { get; set; } public override bool Equals(object obj) { if (obj == null) { return false; } var t = obj as LinkDAO; if (t == null) { return false; } return (t.ObjectA == ObjectA &amp;&amp; t.ObjectB == ObjectB); } public override int GetHashCode() { return (ObjectA.Name + "|" + ObjectB.Name).GetHashCode(); } } </code></pre> <p><em><strong>Mapping File</strong> 'LinkDAO.hbm.xml':</em></p> <pre><code>&lt;class name="LinkDAO" table="LinkTable" lazy="false"&gt; &lt;composite-id&gt; &lt;key-property name="ObjectA" column="id_ObjectA" /&gt; &lt;key-property name="ObjectB" column="id_ObjectB" /&gt; &lt;/composite-id&gt; &lt;/class&gt; </code></pre> <p>I'm querying like this:</p> <pre><code>IList&lt;LinkDAO&gt; links = NHibernateContext.Current().Session.QueryOver&lt;LinkDAO&gt;().List(); //Empty list is returned, but I can check the DB and see records </code></pre> <p><strong>Question:</strong> How do I read the two columns as int values when the table is comprised of only a composite key? (Having references to the actual object would be useful, but the int ids are sufficient)</p>
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    1. This table or related slice is empty.
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    1. USJames
    1. USJames
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
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    1. This table or related slice is empty.
    1. COit seems ObjectA was declared twice in the class LinkDAO
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      1. POHow do I get NHibernate to return data on composite key table?
      1. USdan_l
    2. CO@dan_l Sorry, that appears to be a typo when I removed business specific object names from my code examples. I've since updated the post
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      1. POHow do I get NHibernate to return data on composite key table?
      1. USJames
    3. COhi James . What do you think of the answer I gave below ?
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      1. POHow do I get NHibernate to return data on composite key table?
      1. USdan_l
 

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