text: Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
  ### Context:
  CREATE TABLE Highschooler (id VARCHAR, student_id VARCHAR); CREATE TABLE Friend (id VARCHAR, student_id VARCHAR)
  ### Question:
  Show ids of all students who do not have any friends.
  ### Answer:
  SELECT id FROM Highschooler EXCEPT SELECT student_id FROM Friend