Question

I have to following problem.
I’ve large collection of XML files. In each XML file there are different employees. I have to add the unique employees to the database. In the database each employee has first name, last name and birth date. I want to check whether employee with the same properties already exists in the database and if it doesn’t to insert it.

I’m using the following code:

Entities entities;
entities.AddToEmployee(emp);
entities.SaveChanges();

My employee is connected with another data structure – sales. So I need to add just the employee’s primary key to the sales table but not the whole employee in the database (in case that it already exists).

Thanks in advance!

Answer 1

The ‘Find or Add Pattern’ can be useful in these types of circumstance:

var db = new YourContext();
var emp = db.Employees.Find(empID) ?? db.Employees.Add( new Employee { FirstName ="xx" , LastName="xxx"});
db.SaveChanges();

This way the emp object has been loaded if it exists in the database or created and saved to the database. You might need to replace the Find() with a Where() if you are searching on multiple properties.