You need to add a function that returns the number of years since a person was hired

You use Microsoft visual studio 2010 and Microsoft NET Framework 4 to create an Application. The
application uses the ADO NFT Entity Framework to model entities. The model includes the entity
shown in the following exhibit.

You need to add a function that returns the number of years since a person was hired. You also need
to ensure that the function can be used within LINQ to Entities queries. What should you do?

A.
//Add the following conceptual model function returns the number of years since an instructor
was hired
<Function Name=”YearsSince” ReturnType=”Edm.Int32″>
<Parameter Name=”date” Type=”Edm.DateTime” />
<DefiningExpression>
Year(CurrentDateTime()) – Year(date)
</DefiningExpression>
</Function>

// add the following method to your application and use an EdmFunctionAttribute to map it to the
conceptual model function:
[EdmFunction(“SchoolModel”, “YearsSince”)]
public static int YearsSince(DateTime date)
{
throw new NotSupportedException(“Direct calls are not supported.”);
}

B.
//Add the following conceptual model function returns the number of years since an instructor
was hired
<Function Name=”YearsSince” ReturnType=”Edm.Int32″>
<Parameter Name=”date” Type=”Edm.DateTime” />
<DefiningExpression>
Year(CurrentDateTime()) – Year(date)
</DefiningExpression>
</Function>
// add the following method to your application and use an EdmFunctionAttribute to map it to the
conceptual model function:
[EdmFunction(“SchoolModel”, “YearsSince”)]
public static int YearsSince(DateTime date)
{
return CurrentDateTime() – Year(date);
}

C.
//Add the following conceptual model function returns the number of years since an instructor
was hired
<Function Name=”YearsSince” ReturnType=”Edm.Int32″>
<Parameter Name=”date” Type=”Edm.DateTime” />
<DefiningExpression>
YearsSince(DateTime date)
</DefiningExpression>
</Function>
// add the following method to your application and use an EdmFunctionAttribute to map it to the
conceptual model function:
[EdmFunction(“SchoolModel”, “YearsSince”)]
public static int YearsSince(DateTime date)
{
return CurrentDateTime() – Year(date);
}

D.
Use the Entity Data Model Designer to create a complex property named
YearsSinceNow that can be accessed throuqh the LINQ to Entites query at a Later time

Explanation:
http://msdn.microsoft.com/en-us/library/dd456857.aspx