SQL column values based on values from another table

Question

I'm new to SQL and can't figure this simple thing out. I have two tables:

+----------+----------+
| Person_1 | Person_2 |
+----------+----------+
|        1 |        2 |
|        1 |        4 |
|        3 |        2 |
+----------+----------+

and

+----+------+
| ID | City |
+----+------+
|  1 | A    |
|  2 | B    |
|  3 | A    |
|  4 | A    |
+----+------+

The values in columns Person_A and Person_B refer to the ID in the second table. I want to combine these two tables to have a resulting table like this:

+----------+----------+---------------+---------------+
| Person_1 | Person_2 | Person_1_City | Person_2_City |
+----------+----------+---------------+---------------+
|        1 |        2 | A             | B             |
|        1 |        4 | A             | A             |
|        3 |        2 | A             | B             |
+----------+----------+---------------+---------------+

How can I do this?

Answer 1

Use JOIN with city twice:

select p.persion1, p.persion2, 
  c1.city as persion1city,
  c2.city as persion2city
from  person p
left join city c1 on p.Person_1 = c1.id
left join city c2 on p.Person_2 = c2.id