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POComposite Id's and Restrictions.IdEq or with comparison in Linq not working as expected
 

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    <p>I have an entity where a composite id is used. I changed to code to make use of wrapping the composite id in a seperate key class. I expected that with Linq I could do a comparison on key object and with the Criteria API to use Restrictions.IdEq but both fail. I need to explicitly compare the key values to make it work.</p> <p>I cannot find any documentation if this should work so for the moment I am stuck with direct comparisons but this means that when I alter the key that I also need to update the query code which is obviously not what I would want.</p> <p>As a side note, I tried this with NHibernate 3.0.0 Alpha 2 and 3.</p> <h1>Domain</h1> <h3>Mapping</h3> <pre><code>&lt;?xml version="1.0" encoding="utf-8" ?&gt; &lt;hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="Cwc.Pulse.Dal" namespace="Cwc.Pulse.Dal"&gt; &lt;class name="AddonStatus"&gt; &lt;composite-id name="Id"&gt; &lt;key-many-to-one name="Context" column="Context_Id" class="Context" /&gt; &lt;key-property name="AddonType" column="Addon_Id"/&gt; &lt;/composite-id&gt; &lt;property name="Status" /&gt; &lt;/class&gt; &lt;/hibernate-mapping&gt; </code></pre> <h3>Class</h3> <pre><code>public class AddonStatus { public virtual string Status { get; set; } public virtual Key Id { get; protected set; } public AddonStatus() { Id = new Key(); } public class Key { public virtual Context Context { get; set; } public virtual AddonType AddonType { get; set; } public override int GetHashCode() { return ContextId.GetHashCode() ^ AddonType.GetHashCode(); } public override bool Equals(object obj) { if (this == obj) return true; var o = obj as Key; if (null == o) return false; return Context == o.Context &amp;&amp; AddonType == o.AddonType; } } } </code></pre> <h1>Working queries</h1> <p>The queries below work and as you can see I compare the key values explicitly. I do not compare the key object.</p> <h3>Linq</h3> <pre><code>from status in session.Query&lt;AddonStatus&gt;() where status.Id.Context == context &amp;&amp; status.Id.AddonType == addonType select status </code></pre> <h3>Criteria API</h3> <pre><code>session.CreateCriteria&lt;AddonStatus&gt;() .Add(Restrictions.Eq("Id.Context", context)) .Add(Restrictions.Eq("Id.AddonType", addonType)) </code></pre> <h1>Expected to work but dont</h1> <p>I expect the following queries to work. Either in efficiently for linq in memory instead of the database but I expect the criteria api to be smart enough to handle such composite id´s in queries.</p> <p>Both linq and criteria api queries make use of a Key object comparison.</p> <pre><code>var key = new AddonStatus.Key { Context = context, AddonType = addonType }; </code></pre> <h3>Linq</h3> <pre><code>from status in session.Query&lt;AddonStatus&gt;() where status.Id == key select status </code></pre> <h3>Criteria API</h3> <pre><code>session.CreateCriteria&lt;AddonStatus&gt;() .Add(Restrictions.IdEq(key)) </code></pre> <p>So if anyone has such a scenario working then what am I doing wrong?</p>
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