Question

I have two tables, one called Users and one called Groups. I also have one relationship table called GroupUsers with PK from Groups and Users.

I can add user 1 with group 2 with:

var group = db.Groups.Find(2);
var user = db.Users.Find(1);
group.Users.Add(user);
db.SaveChanges();

But how do I select relations from the GroupUsers table? I want to print out all users that belong to a group using LINQ.

Answer 1

You can easily navigate relationships in Entity Framework using navigation properties.

In this case the Group.Users and User.Groups are navigation properties since they represent the relationship between the Group and User entities.

This example will return all users who belong to the group with primary key value of 1:

db.Groups.Find(1).Users;

See also:

• How to: Navigate Relationships Using Navigation Properties
• Navigation Properties