# 1741. 查找每个员工花费的总时间
# https://leetcode-cn.com/problems/find-total-time-spent-by-each-employee/

# SQL架构
Create table If Not Exists Employees(emp_id int, event_day date, in_time int, out_time int);
Truncate table Employees;
insert into Employees (emp_id, event_day, in_time, out_time) values ('1', '2020-11-28', '4', '32');
insert into Employees (emp_id, event_day, in_time, out_time) values ('1', '2020-11-28', '55', '200');
insert into Employees (emp_id, event_day, in_time, out_time) values ('1', '2020-12-3', '1', '42');
insert into Employees (emp_id, event_day, in_time, out_time) values ('2', '2020-11-28', '3', '33');
insert into Employees (emp_id, event_day, in_time, out_time) values ('2', '2020-12-9', '47', '74');

# Write your MySQL query statement below
select
    event_day as day,
    emp_id as emp_id,
    sum(out_time - in_time) as total_time
from
    Employees
group by
    event_day,
    emp_id
order by
    event_day;

# clean-up
drop table Employees;