任何人都可以帮助查询以下内容?
+-----------+-------------+---------+-------+--------+
| Ticket# | Route | Pairs | Date | Coupon |
+-----------+-------------+---------+-------+--------+
| 123456789 | JFK-LAX-JFK | JFK-LAX | 01Jan | 1 |
| 123456789 | JFK-LAX-JFK | LAX-JFK | 02Feb | 2 |
| 987654321 | LHR-MAN-LHR | LHR-Man | 10Mar | 1 |
| 987654321 | LHR-MAN-LHR | MAN-LHR | 20Apr | 2 |
+-----------+-------------+---------+-------+--------+
返回:
+-----------+-------------+---------+-------+--------+
| Ticket# | Route | Pairs | Date | Coupon |
+-----------+-------------+---------+-------+--------+
| 123456789 | JFK-LAX-JFK | JFK-LAX | 01Jan | 1 |
| 987654321 | LHR-MAN-LHR | LHR-Man | 10Mar | 1 |
+-----------+-------------+---------+-------+--------+
你可以使用row_number()
:
select t.*
from (select t.*
row_number() over (partition by ticket, route order by date) as seq
from table t
) t
where seq = 1;