Question

我找不到正确的sql查询以解决以下问题

这是表格

+------+----------+---------+-------+
| id   | empname  | superid | CTC   |
+------+----------+---------+-------+
|    1 | Sujatha  |       2 | 56000 |
|    2 | Rajesh   |       3 | 60000 |
|    3 | Vasanthi |       4 | 65000 |
|    4 | Murali   |       5 | 75000 |
+------+----------+---------+-------+

我应该打印empname和supervisor名称。 supervisor也是一名员工。

我尝试了几个查询但找不到答案。请帮忙。

我尝试格式化表格，但此平台不允许

Answer 1

您可以通过SELF JOIN

实现此目的

SELECT id AS employeeid
    ,e.empname
    ,s.empname AS supervisor
    ,e.CTC AS employeeCTC
FROM Employees AS e
INNER JOIN Employees AS s ON e.superid = s.id

Answer 2

你可以这样做（如果你的表名是“mytable”例如）：

SELECT emp_table.empname, super_table.empname
FROM mytable emp_table
INNER JOIN mytable super_table ON emp_table.id = super_table.superid

Answer 3

让表名为员工这是查询：

SELECT e1.empname, e2.empname 
FROM employee AS e1 INNER JOIN employee AS e2 
ON e1.superid=e2.id

Answer 4

尝试此查询。

Select empname
, supervisorName 
from employee, supervisor 
where employee.empId=supervisor.empId AND 
     employee.superId=supervisor.superId

Answer 5

SELECT
  em.empname,
  sp.empname
FROM emp_super em
INNER JOIN emp_super sp
  ON em.id = sp.superid

选择columne中具有相同日期的列

5 个答案: