Cannot insert the value NULL into column in ASP.NET MVC Entity Framework

Question

When trying to use this code:

var model = new MasterEntities();

var customer = new Customers();
customer.Sessionid = 25641;

model.Customers.Add(customer);
         


        

Answer 1

I have encountered this problem multiple times while working with Microsoft SQL Server and I have followed the same way to fix it. To solve this problem, make sure Identity Specification is set to Yes. Here's how it looks like:

In this way the column number auto increments as a primary key normally would.

HOW?: right-click the table that contains the column, choose Design, select the primary key and in Column Properties window find Identity Specification and set it to Yes.