I would like to display the data from two different tables in a certain way using postgresql,but I can't think how it should be done. I am not allowed to use JOIN and nested commands The data should be displayed like this:
Country 1
user 1.1
user 1.2 .
.
Country 2
user 2.1
user 2.2
ETC...
CodePudding user response：
If your tables look like this:
| id |
|---|
| 1 |
| 2 |
| 3 |
Then this should work:
select concat('user 1.', id)
from Country1
union all
select concat('user 2.', id)
from Country2