Question

I have 3 tables that I want to join

order table

|   date    | deliver_date |
----------------------------
| 2011-09-01 | 2011-09-13  |
| 2011-09-05 | 2011-09-15  |

deliver table

| deliver_date |
----------------
| 2011-09-01   |
| 2011-09-13   |

return table

|return_date|
--------------
| 2011-09-04 |
| 2011-09-05 |

The data inside 3 tables contains same date.

I want to join the date from 3 tables and display without duplications

The expected result that I want to get something like this

 2011-09-01,2011-09-04,2011-09-05,2011-09-13

Can anyone help me?

Answer 1

You need union not join :

select date from order

union 

select deliver_date from order

union

select deliver_date from deliver

union

select return_date from return