clean

data/2.MySQL中阶/6.子查询/subquery.json → data/2.MySQL中阶/6.子查询/1.相关子查询/subquery.json

 {
   "type": "code_options",
-  "author": "ccat",
+  "author": "Mars Liu",
   "source": "subquery.md",
   "notebook_enable": false,
-  "exercise_id": "98e5d3cb30d94db0bfdca72995648586"
+  "exercise_id": "2fabb69f22224e48a26fec8911798ceb"
 }
\ No newline at end of file

data/2.MySQL中阶/6.子查询/subquery.md

-# 子查询
-
-现有员工表
-
-```mysql
-create table employee
-(
-    id     int primary key auto_increment,
-    name   varchar(256),
-    dept   varchar(256),
-    salary decimal(12, 4)
-)
-```
-
-我们希望找出比销售部（dept 为 sale）工资最高的员工工资更高的那部分人，查询出他们的完整信息，下面哪一项可以满足要求？
-
-## 答案
-
-```mysql
-select id, name, dept, salary
-from employee
-where salary > (select max(salary)
-                from employee
-                where dept = 'sale')
-```
-
-## 选项
-
-### A
-
-```mysql
-select id, name, dept, salary
-from employee
-where dept = 'sale'
-group by dept
-having salary > max(salary)
-```
-
-### B
-
-```mysql
-select l.id, l.name, l.dept, l.salary
-from employee as l
-         join employee as r on l.salary > max(r.salary)
-where r.dept = 'sale'
-group by r.dept 
-```
-
-### C
-
-```mysql
-select id, name, dept, salary
-from employee
-having salary > (select max(salary) from employee where dept = 'sale')
-```
-
-
-