在SQL中,如何显示正在学习多个科目的学生？

Question

例如 - 表名= TABLE

StudentID | SubCode | SubName
-----------------------------
    1          M1       Math
    1          S1       Science
    1          E1       English
    2          H1       History
    3          G2       Geography
    4          M1       Math    

我们可以这样显示答案吗？

studentid | SubCode | SubName
---------------------------------
    1          M1       Math
    1          S1       Science
    1          E1       English

Answer 1

IN()带HAVING子句的子查询应该这样做:

SELECT * 
FROM table
WHERE StudentID IN (
  SELECT 
    StudentID
  FROM table
  GROUP BY userid
  HAVING COUNT(*) > 1
)