title: NHibernate - mapping entity from multiple database tables
body: <p>Is it possible to map an entities properties from different database tables? Say you had the below data model...</p>
  
  <pre><code>[dbo.Albums]              [dbo.Songs]                [dbo.Artists]
  AlbumID int (PK)          SongID int (PK)            ArtistID int (PK)
  AlbumName nvarchar(100)   AlbumID int                ArtistName nvarchar(100)
  .                         SongName nvarchar(50)      .
  .                         Duration int               .
  .                         ArtistID int               .
  .                         .
  </code></pre>
  
  <p>Required entity:</p>
  
  <pre><code>public class Album
  {
      public virtual int AlbumID { get; private set; }
      public virtual string AlbumName { get; set; }
      public List&lt;Song&gt; songs { get; set;}
  }
  
  public class Song
  {
      public virtual int SongID { get; private set; }
      public virtual int AlbumID { get; set; }
      public virtual string SongTitle { get; set; }
      public virtual int Duration { get; set; }
      public virtual ArtistID { get; set; }
      public virtual ArtistName { get; private set; }      &lt;- from different table, read only
  }
  </code></pre>
  
  <p>I know I should probably be creating an Artists entity and attaching that to the Song entity but if the Artists table had lots of columns and all I needed was the ArtistName what's the point in returning all the extra data across the wire when it's not going to be used or updated? I only want the ArtistName for display purposes only.</p>
  
  <p>Thanks, FJ</p>