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PONHibernate wrongly comparing to null when deleting a component
 

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  1. PONHibernate wrongly comparing to null when deleting a component
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    <p>I currently have an issue when updating a component collection on an entity. It was originally mapped as a bag but that was causing all entries to be deleted and reinserted each time. Changing it to a set has fixed that problem but introduced a new one.</p> <p>The component type is called <code>Tracking</code> it has a composite key of <code>UserID</code> and <code>ItemID</code> and two properties which are nullable dates. When one of these is created <code>DateRead</code> set to the current time, it is then replaced later with an entry with the new date on. </p> <p>The underlying SQL NHibernate generates has a where clause which checks that all properties match.</p> <p>The issue is, the other date <code>DateAcknowledged</code> is often null, and the generated SQL seems to have a syntax error, to do a null check its doing this: <code>= NULL</code> rather than: <code>IS NULL</code>, as shown:</p> <pre><code>DELETE FROM TrackingTable WHERE ItemId = 'a68f6dea-1c00-42e2-bc40-9fcf01121bd8' /* @p0 */ AND UserId = 'c8aa41a4-e4c2-4347-ae6e-b48738a53b47' /* @p1 */ AND DateRead = '2012-01-26T12:56:46.00' /* @p2 */ AND DateAcknowledged = NULL /* @p3 */ </code></pre> <p>The thing is, the two dates should not be needed at all to determine what to delete. Simply having the where check item ID and user ID would do.</p> <p>Here is the mapping code where I define the set:</p> <pre><code>Set(x =&gt; x.Trackings, mapper =&gt; { mapper.Key(k =&gt; k.Column("ItemId")); mapper.Table("Tracking"); mapper.Access(Accessor.NoSetter); }, collectionMapping =&gt; collectionMapping.Component(TrackingMap.Mapping())); </code></pre> <p>And here is the mapping for the component:</p> <pre><code>public class TrackingMap { public static Action&lt;IComponentElementMapper&lt;Tracking&gt;&gt; Mapping() { return c =&gt; { c.ManyToOne(x =&gt; x.User, a =&gt; { a.Column("UserId"); a.ForeignKey("UserId"); }); c.Property(x =&gt; x.DateRead); c.Property(x =&gt; x.DateAcknowledged, a =&gt; a.NotNullable(false)); }; } } </code></pre> <p>Is there a way to tell NHibernate to use the keys only on the where clause or for it to compare nulls in the correct way?</p>
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    1. USDan
    1. USBarry Woods
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    1. COcan we see the mapping file?
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    2. COPossible to see the hbm?, for those of us not used to mapping-by-code.
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      1. USDan
 

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