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POPrevent lazy loading in nHibernate
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  1. POPrevent lazy loading in nHibernate
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    copied!<p>I'm storing some blobs in my database, so I have a Document table and a DocumentContent table. Document contains a filename, description etc and has a DocumentContent property.</p> <p>I have a Silverlight client, so I don't want to load up and send the DocumentContent to the client unless I explicity ask for it, but I'm having trouble doing this.</p> <p>I've read the blog post by <a href="http://davybrion.com/blog/2009/03/must-everything-be-virtual-with-nhibernate/" rel="nofollow noreferrer">Davy Brion</a>. I have tried placing lazy=false in my config and removing the virtual access modifier but have had no luck with it as yet.</p> <p>Every time I do a Session.Get(id), the DocumentContent is retrieved via an outer join. I only want this property to be populated when I explicity join onto this table and ask for it. </p> <p>Any help is appreciated.</p> <p>My NHibernate mapping is as follows:</p> <pre><code>&lt;?xml version="1.0" encoding="utf-8" ?&gt; &lt;hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="Jrm.Model" namespace="Jrm.Model"&gt; &lt;class name="JrmDocument" lazy="false"&gt; &lt;id name="JrmDocumentID"&gt; &lt;generator class="native" /&gt; &lt;/id&gt; &lt;property name="FileName"/&gt; &lt;property name="Description"/&gt; &lt;many-to-one name="DocumentContent" class="JrmDocumentContent" unique="true" column="JrmDocumentContentID" lazy="false"/&gt; &lt;/class&gt; &lt;class name="JrmDocumentContent" lazy="false"&gt; &lt;id name="JrmDocumentContentID"&gt; &lt;generator class="native" /&gt; &lt;/id&gt; &lt;property name="Content" type="BinaryBlob" lazy="false"&gt; &lt;column name="FileBytes" sql-type="varbinary(max)"/&gt; &lt;/property&gt; &lt;/class&gt; &lt;/hibernate-mapping&gt; </code></pre> <p>and my classes are:</p> <pre><code>[DataContract] public class JrmDocument : ModelBase { private int jrmDocumentID; private JrmDocumentContent documentContent; private long maxFileSize; private string fileName; private string description; public JrmDocument() { } public JrmDocument(string fileName, long maxFileSize) { DocumentContent = new JrmDocumentContent(File.ReadAllBytes(fileName)); FileName = new FileInfo(fileName).Name; } [DataMember] public virtual int JrmDocumentID { get { return jrmDocumentID; } set { jrmDocumentID = value; OnPropertyChanged("JrmDocumentID"); } } [DataMember] public JrmDocumentContent DocumentContent { get { return documentContent; } set { documentContent = value; OnPropertyChanged("DocumentContent"); } } [DataMember] public virtual long MaxFileSize { get { return maxFileSize; } set { maxFileSize = value; OnPropertyChanged("MaxFileSize"); } } [DataMember] public virtual string FileName { get { return fileName; } set { fileName = value; OnPropertyChanged("FileName"); } } [DataMember] public virtual string Description { get { return description; } set { description = value; OnPropertyChanged("Description"); } } } [DataContract] public class JrmDocumentContent : ModelBase { private int jrmDocumentContentID; private byte[] content; public JrmDocumentContent() { } public JrmDocumentContent(byte[] bytes) { Content = bytes; } [DataMember] public int JrmDocumentContentID { get { return jrmDocumentContentID; } set { jrmDocumentContentID = value; OnPropertyChanged("JrmDocumentContentID"); } } [DataMember] public byte[] Content { get { return content; } set { content = value; OnPropertyChanged("Content"); } } } </code></pre>
 

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