Mapping stored procedures that return custom entity types

In this section, we will discuss how we can use the EDM to map stored procedures that return miscellaneous bits of data. Let's consider a scenario where we need to create an entity that returns the EmployeeID, FirstName, and LastName of all employees who are no longer working in the organization.

To do this, follow these steps:

1. Add a new field of the DateTime type called LeavingDate to the Employee table in the Payroll database.

2. Create a stored procedure called OldEmployees. Here is the script:

       Create procedure OldEmployees
       as
       Select EmployeeID, FirstName, LastName from Employee where LeavingDate is not null

3. Create an entity called OldEmployees in the EDM with the property names matching the corresponding field names of the stored procedure.

4. Create an EntityType called OldEmployees in the CSDL:

       <EntityType Name="OldEmployees">
               <Key>
                 <PropertyRef Name="EmployeeID" />
              ...