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POFluent NHibernate sometimes does not find record (returns null)
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  1. POFluent NHibernate sometimes does not find record (returns null)
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    copied!<p>I fetch a mapped entity with</p> <pre><code>using (var session = myFactory.OpenSession()) { using (var transaction = session.BeginTransaction()) { try{ var myEntity = session.Get&lt;T&gt;(myId); ... transaction.Commit(); if (myEntity == null) throw new ObjectNotFoundException(id, typeof(T)); return myEntity; } catch (HibernateException ex) { // logging if (!transaction.WasCommitted) transaction.Rollback(); throw ex; } } // transaction } // session </code></pre> <p>The problem is that sometimes the entity is found and sometimes not.</p> <p>No entity modification is performed when the program is launched.</p> <p>If I stop the execution after <code>session.Get()</code> and execute the NHibernate generated SQL, the row is found.</p> <p>If I stop the execution after <code>session.Get()</code> and in the Watch section of Visual Studio execute the same statement with another valid id, then the other entity is found, too.</p> <p>After <code>session.Get()</code>, <code>session.IsConnected</code> and <code>session.IsOpen</code> return <code>true</code>.</p> <p>Why does NHibernate not find the entity?</p> <p><strong>EDIT</strong></p> <p>Here are hash code and equals method. The Id is a string.</p> <pre><code>public override int GetHashCode() { int hashCode = 0; hashCode = hashCode ^ Id.GetHashCode(); return hashCode; } public override bool Equals(object obj) { if(obj.GetType()!=typeof(MyEntity)) return false; MyEntity compareTo = obj as MyEntity; return compareTo.Id == this.Id; } </code></pre> <p><strong>EDIT2</strong></p> <p>When the entity is found and I call <code>session.QueryOver&lt;MyEntity&gt;().List().ToList()</code>, then all other entities are found except the one I requested.</p> <p><strong>EDIT3</strong></p> <p>I had defined one relation which was mapped with <code>.Column("colName").Access.ReadOnly()</code>. Now when the program (i.e. a view that uses the entity) was loaded, there was an attempt to update the relation. This, however, probably failed because the relation was not loaded from the database (<code>.Column("colName").Access.ReadOnly()</code>) and the foreign key constraint was not respected. From that point on, the requested entity could not be found anymore.</p> <p>Now I just wonder why my entity could not be loaded when I restarted the application, since the changes (null foreign key reference) was NOT in the database (i.e. the database was still consistent).</p>
 

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