SQL Server Month Totals

Question

SQL Server新手

以下查询仅在学生表中有学生记录的情况下按学生和月份返回SRA。即使学科表中没有学生记录，我也需要一个查询来返回所有学生和月总数。任何方向赞赏

SELECT  TOP 100 PERCENT MONTH(dbo.Discipline.DisciplineDate) AS [Month], dbo.Discipline.StuId, dbo.Stu.Lastname + ',' + dbo.Stu.FirstName AS Student, 
    SUM(CASE WHEN Discipline.SRA = 1 THEN 1 END) AS [Acad Suspension], SUM(CASE WHEN Discipline.SRA = 2 THEN 1 END) AS Conduct, 
    SUM(CASE WHEN Discipline.SRA = 3 THEN 1 END) AS Disrespect, SUM(CASE WHEN Discipline.SRA = 4 THEN 1 END) AS [S.R.A], 
    SUM(CASE WHEN Discipline.SRA = 5 THEN 1 END) AS Suspension, SUM(CASE WHEN Discipline.SRA = 6 THEN 1 END) AS Tone
FROM dbo.Discipline INNER JOIN
     dbo.Stu ON dbo.Discipline.StuId = dbo.Stu.StuId
GROUP BY dbo.Discipline.StuId, dbo.Stu.Lastname, dbo.Stu.FirstName, MONTH(dbo.Discipline.DisciplineDate)
ORDER BY Student

Answer 1

您需要将INNER JOIN更改为dbo.Stu到LEFT JOIN：

   SELECT MONTH(d.disciplinedate) AS [Month], 
          d.StuId, 
          s.Lastname + ',' + s.FirstName AS Student, 
          SUM(CASE WHEN d.SRA = 1 THEN 1 END) AS [Acad Suspension], 
          SUM(CASE WHEN d.SRA = 2 THEN 1 END) AS Conduct, 
          SUM(CASE WHEN d.SRA = 3 THEN 1 END) AS Disrespect, 
          SUM(CASE WHEN d.SRA = 4 THEN 1 END) AS [S.R.A], 
          SUM(CASE WHEN d.SRA = 5 THEN 1 END) AS Suspension, 
          SUM(CASE WHEN d.SRA = 6 THEN 1 END) AS Tone
     FROM dbo.Discipline d
LEFT JOIN dbo.Stu s ON s.stuid = d.stuid
 GROUP BY d.StuId, s.Lastname, s.FirstName, MONTH(d.DisciplineDate)
 ORDER BY Student

LEFT JOIN意味着你左边的任何表都可能没有记录来支持JOIN，但是你仍然会从基表中获取记录（dbo.Discipline）。

我使用了表别名 - d和s。需要指定引用时输入的内容较少。

Answer 2

产生一系列的月份，加入纪律。