mysql SELECT id bank_id MAX first_payment from banks WHERE first_payme

mysql> SELECT id,bank_id,MAX(first_payment) from banks WHERE first_payment <= 50 GROUP BY bank_id
    -> ;
+----+---------+--------------------+
| id | bank_id | MAX(first_payment) |
+----+---------+--------------------+
|  3 |       1 |                 30 | 
|  1 |       2 |                 50 | 
|  5 |       3 |                 50 | 
+----+---------+--------------------+
3 rows in set (0.05 sec)

mysql> select * from banks;
+----+---------+---------------+
| id | bank_id | first_payment |
+----+---------+---------------+
|  1 |       2 |            10 | 
|  2 |       2 |            20 | 
|  3 |       1 |            30 | 
|  4 |       1 |            10 | 
|  5 |       3 |            10 | 
|  6 |       3 |            50 | 
|  7 |       2 |            50 | 
+----+---------+---------------+
7 rows in set (0.00 sec)