Step 1: Create a Stored Procedure Result Set Modelįirst, we’ll create a file called GetEmployeesWithDepartment_Result.cs and define the structure for our complex return type: public class GetEmployeesWithDepartment_Result Note: Before you proceed, scaffold your database using the Scaffold-DbContext command in the Package Manager Console or the dotnet ef dbcontext scaffold command in. We would like to execute this SP from our C# code, so let’s configure EF Core to support calling GetEmployeesWithDepartment as a parameterized SP. >= say we want to determine the department associated with the first employee listed in a simple test database (in our example, the first employee listed is John in Engineering). ![]() Our SP returns the Id value and all of its associated information, such as the employee’s Department and Name values: CREATE OR ALTER PROCEDURE INT Now let’s look at GetEmployeesWithDepartment, an SP that returns an Employee table row matching the input parameter Employee.Id. The ordinal relationships between these tables are: Relationships = Employee(1) : Department(1) and Department(1) : Employees(N) It also references the Department table from the Employee.DepartmentId field connected to the Department table’s Id column. The Employee table references itself through a foreign key from its ManagerId field. Let's consider GetEmployeesWithDepartment, a stored procedure that returns a complex result containing information from two related database tables, Employee and Department: A Hypothetical Stored Procedure With a Complex Result We’ll look at an example stored procedure to see how a few simple adjustments can overcome EF Core’s constraints. NET language that supports EF Core, provided the utility code is translated into that language. NET, Microsoft SQL Server, and EF Core together. We can get around these restrictions by using C#. Make create, update, and delete operations unavailable.Cannot return a complex type in response to a JOIN command.Restrict a stored procedure’s result to an Entity type. ![]() This is due to limitations in EF Core’s out-of-the-box solution that: Microsoft’s Entity Framework (EF) Core can be used to map or import SPs as functions but, unfortunately, EF Core doesn’t natively support the retrieval of complex results from stored procedures. NET developers often need to call a database stored procedure (SP) from their C# server layer.
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