Question

I have a read-only mssql-view, and I want to map it to nhibernate (using hbm.xml files).
The view is a select that joins two tables. For give an abstract-insight, the select is something like this:

SELECT A.Id As A_ID, B.Id As B_ID,
       A.AttributeA, B.AttributeB,

FROM A INNER JOIN B ON 
     A.Id = B.RootID

It’s a one-to-many relationship between A and B (B entries are dependant/leafs of A entries).

I’m using nhibernate’s hbm.xml files, and I can’t make it to work.

I’d gladly appreciate if someone can enlight me of the kind of XML that I have to use, I guess that as my view has no ID, I have to create a composite-nhibernate id (wich will be the ids os A and B together) but I couldn’t make it to work.
Also the view is READ ONLY so I think that should make the solution easier.

I’m asking the question because none of the others on the site answered this issue (some use fluent-nhibernate,I’m with XML mapping files)

thanks in advance.

Answer 1

Thanks to Andy, that lead me to the final solution.
I will put the hbm.xml template with my domain-model entities.
All the columns I’m mapping are varchars/strings (hence my composite ID consist of two strings):

    <class name="Model.Projects.ProjectsLoansView"
           table="V_PROJECTSLOANS" mutable="false">

    <composite-id>
      <key-property name="Number" column="Number"/>
      <key-property name="OperationNumber" column="OperationNumber" />
    </composite-id>

    <property name="Name" column="Name" not-null="false"/>

  </class>

But the mapping was not enough. Nhibernate requests to Override the Equals and GetHashCode function, I will put the exact code of my working VB.Net class that correspond to this XML:

  Public Class ProjectsLoansView

        Public Overridable Property Number As String
        Public Overridable Property OperationNumber As String

        Public Overridable Property Name As String

        Public Overloads Overrides Function Equals(ByVal obj As Object) As Boolean

            If (IsNothing(obj)) Then Return False

            Dim t As ProjectsLoansView = CType(obj, ProjectsLoansView)

            If ((Me.Number = t.Number) And (Me.OperationNumber = t.OperationNumber)) Then
                Return True
            Else
                Return False
            End If
        End Function

        Public Overrides Function GetHashCode() As Integer
            'TODO: check how to override properly GetHashCode. As is a-read only view it doesn't matter here
            Return MyBase.GetHashCode()
        End Function

    End Class