我正在尝试将一个薪水与另一个薪水进行比较，并添加评论栏以显示其薪水高于谁。
我使用自我联接进行比较，但我不知道如何包含一个评论专栏来解释谁比谁更高。
期待如下所示：
empid name salary comments
1 raj 30000 "raj sal less then dev and sunil but greater then prashant,dilip,anil"
2 prashant 24935 "prashant sal less then raj,dev,anil,sunil but greather then dilip"
3 dev 38572
4 anil 29845
5 sunil 48201
6 dilip 12093
答案 0 :(得分：0)
在STUFF声明中使用CASE功能。
SELECT t1.empid, t1.name, t1.salary,
CASE WHEN t1.salary = (SELECT MIN(t3.salary) FROM yourtable t3)
THEN t1.name + ' has the lowest salary.'
WHEN t1.salary = (SELECT MAX(t3.salary) FROM yourtable t3)
THEN t1.name + ' has the highest salary.'
ELSE t1.name +'''s salary is less than ' + STUFF((SELECT ', ' + CAST(T2.name AS VARCHAR(MAX))
FROM yourtable T2 WHERE T1.salary < T2.salary
FOR XML PATH('')),1,1,'') + ' but greater than ' + STUFF((SELECT ', ' + CAST(T2.name AS VARCHAR(MAX))
FROM yourtable T2 WHERE T1.salary > T2.salary
FOR XML PATH('')),1,1,'') + '.'
END AS Comments
FROM yourtable t1
GROUP BY t1.empid, t1.name, t1.salary
输出
empid name salary Comments
1 raj 30000 raj's salary is less than dev, sunil but greater than prashant, anil, dilip.
2 prashant 24935 prashant's salary is less than raj, dev, anil, sunil but greater than dilip.
3 dev 38572 dev's salary is less than sunil but greater than raj, prashant, anil, dilip.
4 anil 29845 anil's salary is less than raj, dev, sunil but greater than prashant, dilip.
5 sunil 48201 sunil has the highest salary.
6 dilip 12093 dilip has the lowest salary.