mysql> desc t;
+---------+---------+------+------+---------+-------+
| Field   | Type    | Null | Key  | Default | Extra |
+---------+---------+------+------+---------+-------+
| from_id | int(11) | YES  |      | NULL    |       |
| to_id   | int(11) | YES  |      | NULL    |       |
| value   | int(11) | YES  |      | NULL    |       |
+---------+---------+------+------+---------+-------+
mysql> select count(*) from t;
+----------+
| count(*) |
+----------+
|   393216 |
+----------+
mysql> select count(*), from_id, to_id, value from t group by from_id, to_id, value;
+----------+---------+-------+-------+
| count(*) | from_id | to_id | value |
+----------+---------+-------+-------+
|   131072 |       2 |     3 |     2 |
|   131072 |       3 |     4 |     3 |
|   131072 |       1 |     2 |     1 |
+----------+---------+-------+-------+

mysql>  select count(*) from t t1 join t t2 on t1.from_id = t2.to_id and t1.value > t2.value;
+-------------+
| count(*)    |
+-------------+
| 34359738368 |
+-------------+
1 row in set (1 min 5.94 sec)

mysql>  select count(*) from t t1 join t t2 on t1.from_id = t2.to_id and t1.value > t2.value;
+-------------+
| count(*)    |
+-------------+
| 34359738368 |
+-------------+
1 row in set (52.86 sec)

None