mysql>
mysql>
mysql> --
mysql> SELECT count(tour_id) AS cnt
-> FROM orders
-> JOIN tours
-> ON orders.tour_id=tours.id
-> GROUP BY tour_id;
+-----+
| cnt |
+-----+
| 1 |
| 4 |
| 2 |
| 1 |
| 1 |
+-----+
5 rows in set (0.00 sec)
mysql>
mysql>
mysql> --
mysql> select cnt
-> from (select count(o.tour_id) as cnt
-> from orders o, tours t
-> where o.tour_id = t.id
-> group by o.tour_id) p
-> where cnt = (select min(cnt)
-> from (select count(o.tour_id) as cnt
-> from orders o, tours t
-> where o.tour_id = t.id
-> group by o.tour_id
-> ) p
-> );
+-----+
| cnt |
+-----+
| 1 |
| 1 |
| 1 |
+-----+
3 rows in set (0.00 sec)
mysql>
mysql>