title: Fluent nHibernate Join
body: <p>I have an entity that maps to a table called Rule.  The table for this entity has an FK to another Table called Category.  I'm trying to figure out how to pull in a property from Category in my Rule entity.  I'm pretty sure I want to use a join in my entity mapping, but I can't figure out how to configure it so that it works.  Here is my mapping:</p>
  
  <pre><code>Join("Category", x =&gt; 
  {
      x.Map(i =&gt; i.CategoryName, "Name");
      x.KeyColumn("CategoryId");
      x.Inverse();
  });
  </code></pre>
  
  <p>Here is the SQL that it's generating...</p>
  
  <pre><code>SELECT ...
  FROM Rule rules0_ left outer join Category rules0_1_ on rules0_.Id=rules0_1_.CategoryId
  WHERE ...
  </code></pre>
  
  <p>Here is the SQL that I want.</p>
  
  <pre><code>SELECT ...
  FROM Rule rules0_ left outer join Category rules0_1_ on rules0_.CategoryId=rules0_1_.Id
  WHERE ...
  </code></pre>
  
  <p>I can't seem to find anything on the JoinPart that will let me do this.  Subselect looks promising from the little bit of documentation I've found, but I can't find any examples of how to use it.  Any advice on this problem would be much appreciated.  Thanks!</p>