I tried inner joining one table on another. It's joining side by side. Is there any alternative-CodePudding

I have inner-joined two tables on 1 column. As per the method, it'll join side by side. For example

there are two tables employee(id, date, department) employee_1(id, date, department)

Let's take the employee data below

id   date         department
1    2022-09-09   professor
2    2022-10-08   professor
3    2022-10-11   professor
3    2022-09-02   professor

And employee_1 table is below

id   date         department
1    2021-09-09   professor
2    2021-10-08   professor
3    2021-10-11   professor
3    2021-09-02   professor
4    2021-09-10   professor

If I inner join the above two tables with the below query

select employee.*, employee_1.* from employee 
inner join employee_1
on employee.id = employee_.id

It'll return below table

id   date         department   date 
1    2022-09-09   professor   2022-09-09
2    2022-10-08   professor   2022-10-08
3    2022-10-11   professor   2022-10-11 
3    2022-09-02   professor   2021-09-02

How to get the output like

id       date         department
1    2022-09-09   professor  
2    2022-10-08   professor   
3    2022-10-11   professor   
3    2022-09-02   professor 
1    2021-09-09   professor
2    2021-10-08   professor
3    2021-10-11   professor
3    2021-09-02   professor

How to get the above table as output?

CodePudding user response：

select id, date, department
from employee
union all
select id, date, department
from employee_1