Something like this ought to function since you already have the question ids to delete:...// assuming db is your DbContext
var questions = db.QuizWithQuestions
.Where(q => deletedQuestions.Contains(q.Id))
.Include(q => q.QuizUserAnswers);
// assuming this is your DbSet
I wanted to switch from only IDs to GUIDs for uniqueness and changed the tables. ...To assure uniqueness, you don't really need to convert to GUIDs. As long as they are configured as your main keys, your IDs (regardless of what type they are, like integers), will be assured to be distinct....I have read that GUIDs as primary keys are not recommende...