如何根据多个最大日期列选择整行

Question

我想要选择整行，它已经被最多2个日期列过滤-

因此，如果我有一个表(供应)：

D_id |O_id  | O_date    | Start_date| amount 
400  |1     | 2018-2-7  | 2018-4-7  | 500
401  |1     | 2019-8-2  | 2019-10-1 | 1500
402  |1     | 2019-8-2  | 2019-12-7 | 200
403  |2     | 2016-4-10 | 2016-5-7  | 100
404  |2     | 2018-12-1 | 2018-12-17| 50
405  |2     | 2018-12-1 | 2019-1-1  | 2500

因此，输出应按d_id分组，并显示具有最大O_date和最大start_date的整行

D_id |O_id  | O_date    |  Start_date | amount |
402  |1     | 2019-8-2  | 2019-12-7   | 200
405  |2     | 2018-12-1 | 2019-1-1    | 2500

我一直面临的问题是，由于使用了max和group by条件，SQL使每一行的字段都不匹配。

select max(O_DATE),
MAX(START_DATE),
D_ID,
AMOUNT,
O_ID
FROM SUPPLY
group by
O_ID;

Answer 1

下面的查询应该适用于您。对于您的逻辑来说，START_DATE在这两种情况下都是常见的，并且只有START_DATE之间的连接应该可以做到这一点。

SELECT * FROM SUPPLY A
INNER JOIN 
(
    SELECT O_ID,
    MAX(O_DATE) O_DATE,
    MAX(START_DATE) START_DATE
    FROM SUPPLY
    group by O_ID
)B 
ON A.O_ID = B.O_ID
AND A.START_DATE = B.START_DATE

Answer 2

这就是您要查找的内容：

select
 t1.D_id, t1.O_id, t2.o_date, t2.Start_date, t1.amount 
from SUPPLY t1
outer apply (
     select O_id, Max(O_date) as o_date, MAX(Start_date) as Start_date from SUPPLY
        group by O_id
) as t2 where t2.O_id = t1.O_id and t2.o_date = t1.O_date and t2.Start_date = t1.Start_date

Answer 3

您可以通过将查询连接到表来完成此操作：

SELECT s.* 
FROM SUPPLY s INNER JOIN (
  SELECT 
    max(O_DATE) O_DATE,
    max(START_DATE) START_DATE
  FROM SUPPLY
  GROUP BY O_ID
) g ON g.O_ID = s.O_ID AND g.O_DATE = s.O_DATE AND g.START_DATE = s.START_DATE

或者使用NOT EXISTS：

SELECT s.* 
FROM SUPPLY s 
WHERE NOT EXISTS (
  SELECT 1 FROM SUPPLY
  WHERE O_ID = s.O_ID AND O_DATE > s.O_DATE AND START_DATE > s.START_DATE 
)