使用Microsoft SQL Server基于列更新另一个表中的表

Question

嘿，我有两张桌子。具有我需要传输到Employee表（GradeID）的数据（gID）的成绩表。

雇员

EmployeeID  | Name       | mgr | Job         | Salary| Comm | HireDate     | dID| GradeID
1001 | Susan Adams   | 1004| Locksmith| 60000| 20000| 2005-04-12| 1  | NULL
1002 | Ricky Jones    | 1004| Writer| 85000 | 15000| 2020-01-18| 1  | NULL
1003 | Beatrice    | 1006| Editor| 89000 | NULL | 2002-03-07| 2  | NULL


GradeID| MinSal| MaxSal| Holiday
A  | NULL  | 60000 | 40
B  | 60000 | 80000 | 40
C  | 90000 | 100000| 40
D  | 200000| 120000| 45
E  | 320000| NULL  | 55

这就是我到目前为止所拥有的

UPDATE EMPLOYEE
SET GradeID = 'A'
WHERE Salary between (SELECT COALESCE(MAX(MinSAL),0) From GRADE WHere gID = 'A') and (SELECT Max (MaxSal) From GRADE where gID = 'A')

UPDATE EMPLOYEE
SET GradeID = 'B'
WHERE Salary between (SELECT MAX(MinSal) From GRADE WHere gID = 'B') and (SELECT Max (MaxSal) From GRADE where gID = 'B')

UPDATE EMPLOYEE
SET GradeID = 'C'
WHERE Salary between (SELECT MAX(MinSal) From GRADE WHere gID = 'C') and (SELECT Max (MaxSal) From GRADE where gID = 'C')

UPDATE EMPLOYEE
SET GradeID = 'D'
WHERE Salary between (SELECT MAX(MinSal) From GRADE WHere gID = 'D') and (SELECT Max (MaxSal) From GRADE where gID = 'D')

UPDATE EMPLOYEE
SET GradeID = 'E'
WHERE Salary between (SELECT MAX(MinSal) From GRADE WHere gID = 'E') and (SELECT COALESCE(MAX(MaxSAL),1000000000000000) From GRADE WHere gID = 'E')

但是我需要一个不那么笨重的单个查询，可以根据他们的工资填充Employee表中的正确等级。谢谢你的帮助。

Answer 1

尝试使用更新联接：

UPDATE e
SET e.GradeID = g.gID
FROM Employee e
INNER JOIN Grade g
    ON (e.Salary > g.MinSal OR g.MinSal IS NULL) AND
       (e.Salary <= g.MaxSal OR g.MaxSal IS NULL);