最喜歡的課程查詢

Question

我不知道我會怎麼做：

我有三個表：

Student(StudentID, StudentName) 
Course(CourseID, CourseName) 
StudentCourse(StudentID, CourseID) -- junction table to assign courses to students 

我將如何查詢來獲取基礎上，在最喜歡的課程條件 即「入學人數最多的課程是 最喜歡的課程」

幫助??

我已經安裝的模式在SQL小提琴

SQLFiddle

Answer 1

SELECT TOP 1 WITH TIES COURSEID 
FROM STUDENTCOURSE 
GROUP BY COURSEID 
ORDER BY Count(*) DESC 

Answer 2

使用TOP...WITH TIES

SELECT TOP 1 WITH TIES c.CourseName, 
     COUNT(c.CourseID) totalCount 
FROM student a 
     INNER JOIN studentcourse b 
      ON a.studentID = b.studentID 
     INNER JOIN course c 
      ON b.courseID = c.courseID 
GROUP BY c.CourseName 
ORDER BY totalCount DESC 

WITH TIES嘗試它表明，擁有數相同數量的最高記錄。

SQLFiddle Demo