Many to many relation linq query in EF

Question

I have 3 tables Student, Course, and the linking table StudentCourse, how do i return all the courses given a student Id = 1 but also include row where the student id might not

Answer 1

Given that this is EF and your latest clarification you should have a Courses navigation property on your Student entity and a Students navigation on your Course entity that would allow you to do the following:

var students =  db.Students
                  .Single(x=> x.Id == 1)
                  .Courses.SelectMany(c=> c.Students)
                  .Distinct();