mysql - Mysql 查找飞机名称，使所有获得驾驶资格的飞行员的收入超过 80,000 美元

Question

1. 以下关系跟踪航空公司航类信息:

   FLIGHTS(flno: integer, from: string, to: string, distance: integer, departs:time,arrives: time, price: integer)
   AIRCRAFT(aid: integer, aname: string, cruisingrange: integer) CERTIFIED(eid: integer, aid: integer) EMPLOYEES(eid: integer, ename: string, salary: integer)

注意:-员工关系也描述了飞行员和其他类型的员工；每个飞行员都获得了某些飞机的认证，并且只有飞行员获得了某些飞机的认证 飞翔。

问题:找到飞机的名称，使所有获得操作这些飞机资格的飞行员的收入超过 80,000 美元。

帮我解决这个问题。我的问题是

SELECT  DISTINCT A.aname FROM  AIRCRAFT A WHERE  A.Aid IN 
( SELECT C.aid FROM CERTIFIED C, EMPLOYEES E WHERE C.eid = E.eid AND NOT EXISTS 
( SELECT * FROM EMPLOYEES E1 WHERE E1.eid = E.eid AND E1.salary < 80000 )) ;

即使该航类的任何员工的收入低于 80,000，此查询也会给出航类名称。

Answer 1

SELECT distinct aname FROM aircraft
 JOIN certified ON aircraft.aid = certified.aid
 JOIN employees ON employees.eid = certified.eid
WHERE employees.salary> 80000
 AND aircraft.aid NOT IN 
(SELECT aircraft.aid FROM aircraft
 JOIN certified ON aircraft.aid = certified.aid
 JOIN employees ON employees.eid = certified.eid
WHERE employees.salary <= 80000)