在 Sql Developer 中组合相似的字段？

Question

我目前有一个查询如下：

SELECT c.Course_No
       , c.Description
       ,  e.Section_Id
       , COUNT(e.Section_ID) AS enrollment
FROM Enrollment e JOIN
     Section s
     ON e.Section_Id = s.Section_Id JOIN
     Course c
     ON s.Course_No = c.Course_No
Group by c.Course_No, c.Description, e.Section_Id
ORDER BY c.Course_No

它工作正常，这里是结果的sn-p：

COURSE_NO              DESCRIPTION                                        SECTION_ID             ENROLLMENT             
---------------------- -------------------------------------------------- ---------------------- ---------------------- 
10                     Technology Concepts                                80                     1                      
20                     Intro to Information Systems                       81                     3                      
20                     Intro to Information Systems                       82                     2                      
20                     Intro to Information Systems                       83                     2                      
20                     Intro to Information Systems                       84                     2           

我对你们的问题是：有没有办法组合具有相同课程描述和不同 sectionID 的字段？我想将所有字段组合起来，但我不太确定该怎么做。

添加提示和预期结果：生成一个字母列表，其中包含在第 90 节期末考试中得分高于平均水平的学生的姓氏和期末考试成绩 (FI)。

LAST_NAME                 NUMERIC_GRADE
------------------------- -------------
Da Silva                             92
Lopez                                91 

Answer 1

我想你想要这样的东西：

SELECT c.Course_No, c.Description, 
       LISTAGG(e.Section_Id, ',') WITHIN GROUP (ORDER BY e.Section_Id) as sections,
       COUNT(*) AS enrollment
FROM Enrollment e JOIN
     Section s
     ON e.Section_Id = s.Section_Id JOIN
     Course c
     ON s.Course_No = c.Course_No
Group by c.Course_No, c.Description
ORDER BY c.Course_No