I have 2 tables
+------+-------+-------+-------+-------+
| id | start | end | pointA| pointB|
+------+-------+-------+-------+-------+
| 1 | xxx | xx | 1 | 2 |
| 2 | xxx | xx | 2 | 1 |
+------+-------+-------+-------+-------+
+------+-------------+
| id | desc |
+------+-------------+
| 1 | "Chicago" |
| 2 | "NYC" |
+------+-------------+
So for example:
When a person rides from point A to point B it gets registerd in the rides
table. pointA
and pointB
are both FK's in the rides
table from the table points
How is it possible to get an SQL output in MySQL
like this for a ride where id = 1
for example:
+------+-------+-------+-------+-------+
| id | start | end | pointA| pointB|
+------+-------+-------+-------+-------+
| 1 | xxx | xx |Chicago| NYC |
You can join the same table twice, by giving each one a different alias:
SELECT r.id, r.start, r.end, pA.desc as pointA, pB.desc as pointB
FROM rides r
JOIN points pA ON pA.id = r.pointA
JOIN points pB ON pB.id = r.pointB
WHERE r.id = 1;
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