Question

Working on a website that has Employee and Branch entities, using a database table “Employees” which also contains the branch id and branch name. I can’t change the client’s database so I need to map Employees and Branches from the same table.

I guess I need some type of distinct clause in the mapping XML to get a distinct list or set of branches from the employee table?

Is there a way I can map both classes on the same table? (Can it be done with Fluent NHibernate?)

Answer 1

Use components. I don’t know FluentNhibernate, but in xml, it looks like this:

<class name="Employee">
  ...

  <component name="MyBranch">
    <!-- Branche properties are here: -->
    <property name="BrancheName"/>
    <property name="..."/>
  </component>
</class>

class Employee
{
  Branch MyBranch { get; private set; }
}

class Branch
{
  string BrancheName { get; private set; }
}

It’s actually pretty straight-forward. You also do this for performance reasons, because you don’t need to join tables when there is always a branch on an employee.

Note: If all columns are null, myBranch will be null.