text: DROP SCHEMA IF EXISTS LeetCode;
  CREATE SCHEMA LeetCode;
  USE LeetCode;
  
  Create table If Not Exists salary (id int, employee_id int, amount int, pay_date date);
  Create table If Not Exists employee (employee_id int, department_id int);
  
  Truncate table salary;
  insert into salary (id, employee_id, amount, pay_date) values ('1', '1', '9000', '2017/03/31');
  insert into salary (id, employee_id, amount, pay_date) values ('2', '2', '6000', '2017/03/31');
  insert into salary (id, employee_id, amount, pay_date) values ('3', '3', '10000', '2017/03/31');
  insert into salary (id, employee_id, amount, pay_date) values ('4', '1', '7000', '2017/02/25');
  insert into salary (id, employee_id, amount, pay_date) values ('5', '2', '6000', '2017/02/28');
  insert into salary (id, employee_id, amount, pay_date) values ('6', '3', '8000', '2017/02/28');
  
  Truncate table employee;
  insert into employee (employee_id, department_id) values ('1', '1');
  insert into employee (employee_id, department_id) values ('2', '2');
  insert into employee (employee_id, department_id) values ('3', '2');