Part 7 - Using stored procedures with entity framework

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In this video we will discuss using our own custom stored procedures to perform Insert, Update and Delete operations using entity framework. We will be using the following Employees table for this demo.





Step 1: Use the following SQL Script to create and populate Employee table.

Create table Employees

(

     ID int primary key identity,

     Name nvarchar(50),

     Gender nvarchar(50),

     Salary int

)

Insert into Employees values ('Mark', 'Male', 60000)

Insert into Employees values ('Steve', 'Male', 45000)

Insert into Employees values ('Ben', 'Male', 70000)

Insert into Employees values ('Philip', 'Male', 45000)

Insert into Employees values ('Mary', 'Female', 30000)

Insert into Employees values ('Valarie', 'Female', 35000)

Insert into Employees values ('John', 'Male', 80000)

Step 2: Create Insert, Update and Delete stored procedures

Create procedure InsertEmployee

@Name nvarchar(50),

@Gender nvarchar(50),

@Salary int

as

Begin

     Insert into Employees values (@Name, @Gender, @Salary)   

End

Go

Create procedure UpdateEmployee

@ID int,

@Name nvarchar(50),

@Gender nvarchar(50),

@Salary int

as

Begin

     Update Employees Set Name = @Name, Gender = @Gender,

     Salary = @Salary

     where ID = @ID

End

Go

Create procedure DeleteEmployee

@ID int

as

Begin

     Delete from Employees where ID = @ID

End

Go

Step 3: Create a new empty asp.net web application

Step 4: Add a new ADO.NET Entity Data Model.
a) On Choose Model Contents screen select "Generate from database" option and click Next


b) On "Choose Your Data Connections" screen give a meaningful name for the connection string that will be stored in the web.config file. I have named it EmployeeDBContext. Click Next.


c) On "Choose Your Database Objects" screen, select Employees Table and the 3 stored procedures (InsertEmployee, UpdateEmployee, DeleteEmployee). Provide a meaningful name for the Model namespace. I have named it EmployeeModel. CLick Finish.


At this point on the ADO.NET Entity Model designer surface, we should be able to see the Employee entity but not the stored procedures. 

To view the stored procedures, 
1. Right click on entity model designer surface and select "Model Broswer" from the context menu.

2. Expand Stored Procedures folder


Step 5: Add a web form to the project. Drag and drop the following 3 controls and build the solution.
1. GridView
2. DetailsView
3. EntityDataSource

Step 6: Configure EntityDataSource control

a). Right click on EntityDataSource control and select "Show Smart Tag" option

b) Click on Configure Data Source link

c) Select EmployeeDBContext from the Named Connection dropdownlist and click Next

d) Select the options on "Configure Data Selection" screen as shown in the image below and click Finish


Step 7: Configure GridView control

a). Right click on GridView control and select "Show Smart Tag" option

b) Click on "Auto Format" link and select "Colourful" scheme

c) Select "EntityDataSource1" from "Choose Data Source" dropdownlist

d) Select Enable Editing and Enable Deleting checkboxes


Step 8: Configure DetailsView control
a) Right click on DetailsView control and select "Show Smart Tag" option
b) Click on "Auto Format" link and select "Colourful" scheme
c) Select "EntityDataSource1" from "Choose Data Source" dropdownlist
d) Select Enable Inserting checkbox
e) Set DeafultMode=Insert. Use properties window to set this.
f) Set InsertVisible="false" for the ID BoundField. You can do this directly in the HTML Source.
g) Generate ItemInserted event handler method for DetailsView control. Copy and paste the following code.

protected void DetailsView1_ItemInserted (object sender, DetailsViewInsertedEventArgs e)

{

    GridView1.DataBind();

}

At this point if you run the application, and if you insert, update and delete employees, by default entity framework will use the sql it auto-generates and not our custom stored procedures.

To tell the entity framework to use the stored procedures, we have to map them to the Employee entity. 

Here are the steps.
1. Right click on "Employee" entity on "EmployeeModel.edmx" and select "Stored Procedure Mapping" option from the context menu.

2. In the "Mapping Details" windows specify the Insert, Update and Delete stored procedures that you want to use with "Employee" entity


At this point, 
1. Run SQL Prrofiler
2. Run the application
3. Insert, Update and Delete Employee, and notice that the respective stored procedures are being called now.