Question

情况

我有一个典型的MS Access数据库，其中包含有关公司，薪酬，员工和职位的信息。一些表格是：

tbl_Report（Report_ID PK，Report_Year）
tbl_Employee（Employee_ID PK）
tbl_Pay（Pay_ID PK，Salary，Employee_ID FK，Report_ID FK）
tbl_Position（Position_ID PK，Position，Employee_ID FK，Report_ID FK）

我有一个查询，为每个职位和年份选择薪水，以生成：

qry_Salary_by_Position_Year:   (This query is parameterised to accept a 'Year').

Year | Salary | Position
------------------------
2014 |  100   |   CEO
2013 |  200   |   CEO
2014 |  300   |   CFO
2014 |  200   |  Chairman
2013 |  150   |   CEO

etc.

然后我使用另一个查询来提取给定位置的工资的前x％：

qry_Select_Top_25:

SELECT TOP 25 PERCENT Salary, Year, Position
FROM qry_Salary_by_Position_Year;

给出了类似的东西：

Salary | Year | Position
------------------------
 100   | 2014 |  CEO
 100   | 2014 |  CFO
 200   | 2014 |  CFO

问题

我想要的是一个决赛桌，显示Max（25％），Max（50％），Max（75％），Max（X％）值，按职位和年份分组，例如：

Year | Position | 25th | 50th | 75th 
-------------------------------------
2013 |   CEO    |  10  |  30  |  75  
2014 |   CEO    |  20  |  50  |  80  
2014 |   CFO    |  15  |  30  |  90
2014 | Chairman |  20  |  25  |  30

我可以使用

SELECT Year, Position, Max(qry50.Salary) AS 50_Percentile
FROM (SELECT TOP 50 PERCENT qry_Salary_by_Position_Year.Salary, Year, Position 
FROM qry_Salary_by_Position_Year)  AS qry50
WHERE Position IN  (SELECT DISTINCT Position FROM qry_Salary_by_Position_Year) AND Year IN (SELECT DISTINCT Year FROM qry_Salary_by_Position_Year)
GROUP BY Year, Position;

但我无法理解如何使用正确的别名等构建查询，以将其他百分比值添加为其他列。有没有人有任何建议/意见/问题？

修改

我可能已经提出了一个我现在正在检查的解决方案：

SELECT qry.Year, qry.Position, Max(qry25.Salary) AS 25_Percentile, Max(qry50.Salary) AS 50_Percentile, Max(qry75.Salary) AS 75_Percentile, Max(qry100.Salary) AS 100_Percentile
FROM 
((((qry_Salary_by_Position_Year qry
LEFT OUTER JOIN (SELECT TOP 50 PERCENT  Salary, Year, Position FROM qry_Salary_by_Position_Year) AS qry50 ON qry.Year = qry50.Year AND qry.Position = qry50.Position)
LEFT OUTER JOIN (SELECT TOP 25 PERCENT Salary, Year, Position FROM qry_Salary_by_Position_Year) AS qry25 ON qry.Year = qry25.Year AND qry.Position = qry25.Position)
LEFT OUTER JOIN (SELECT TOP 75 PERCENT Salary, Year, Position FROM qry_Salary_by_Position_Year) AS qry75 ON qry.Year = qry75.Year AND qry.Position = qry75.Position)
LEFT OUTER JOIN (SELECT TOP 100 PERCENT Salary, Year, Position FROM qry_Salary_by_Position_Year) AS qry100 ON qry.Year = qry100.Year AND qry.Position = qry100.Position)
GROUP BY qry.Year, qry.Position

Answer 1

我认为这就是我之后的事情：

SELECT qry.Year, qry.Position, Max(qry25.Salary) AS 25_Percentile, Max(qry50.Salary) AS 50_Percentile, Max(qry75.Salary) AS 75_Percentile, Max(qry100.Salary) AS 100_Percentile
FROM 
((((qry_Salary_by_Position_Year qry
LEFT OUTER JOIN (SELECT TOP 50 PERCENT  Salary, Year, Position FROM qry_Salary_by_Position_Year) AS qry50 ON qry.Year = qry50.Year AND qry.Position = qry50.Position)
LEFT OUTER JOIN (SELECT TOP 25 PERCENT Salary, Year, Position FROM qry_Salary_by_Position_Year) AS qry25 ON qry.Year = qry25.Year AND qry.Position = qry25.Position)
LEFT OUTER JOIN (SELECT TOP 75 PERCENT Salary, Year, Position FROM qry_Salary_by_Position_Year) AS qry75 ON qry.Year = qry75.Year AND qry.Position = qry75.Position)
LEFT OUTER JOIN (SELECT TOP 100 PERCENT Salary, Year, Position FROM qry_Salary_by_Position_Year) AS qry100 ON qry.Year = qry100.Year AND qry.Position = qry100.Position)
GROUP BY qry.Year, qry.Position

我通过对另一篇文章的回答引出了这个解决方案：https://stackoverflow.com/a/7855015/4002530

SQL嵌套的选择和别名

1 个答案: