mSSQL、SQL查看、select、百分比查询

Question

所以这是我需要满足的要求： ESD 中所有学校的汇总数据，按

分组

SchoolDistrict.SchoolDistrictID

(得到和上面学区场景一样的数据，然后加上按区分组，筛选到

EducationServiceDistrict. EducationServiceDistrictID

) 还计算通过、失败和未测试的百分比

如何计算通过、失败和未测试的百分比？这是我到目前为止编写的查询。

CREATE VIEW district_map AS  
 SELECT * and SchoolDistrictID, 
        EducationServiceDistrict
   FROM SchoolDistrict_View  
         and SchoolDistrict, 
        EducationServiceDistrict
  GROUP BY EducationServiceDistrict.EducationServiceDistrictID  
  ORDER BYLeadWaterTestLocation.PassFail

Answer 1

这是解决这些问题的一般思路 - 如果您理解这个简化版本，您将能够解决您的问题。

    select d.districtName,
    s.studentCount,
    case when s.studentCount=0 then 0 else s.passed / s.studentCount * 100 end as PassedPct
    from district d 
    join (select districtId,
          sum(studentCount) as studentCount,
          sum(passed) as passed
          from schools
          group by districtId) as s
    on d.districtId = s.districtId
    order by d.districtName

mSSQL、SQL查看、select、百分比查询

mSSQL, SQL view, select, percentage query

sql

sql-server

select

percentage

calculation