Question

我对mysql中的SQl查询有疑问。我想选择最近日期时间为id = 1或id = 3的两行

表记录

 id   |  datetime                |          count
 -------------------------------------------------------
 1    |  2018-01-02 11:00:00     |           1
 2    |  2018-01-02 11:00:00     |           0
 3    |  2018-01-02 11:00:00     |           1
 1    |  2018-01-02 10:55:00     |           0
 2    |  2018-01-02 10:55:00     |           0
 3    |  2018-01-02 10:55:00     |           0
 1    |  2018-01-02 10:50:00     |           1
 2    |  2018-01-02 10:50:00     |           1
 3    |  2018-01-02 10:50:00     |           1

我希望我的查询能够重新开始最近的交易：

     id    |  datetime                |          count
 -------------------------------------------------------
      1    |  2018-01-02 11:00:00     |           1
      3    |  2018-01-02 11:00:00     |           1

有人可以给我任何建议吗？

Answer 1

尝试联盟

SELECT *
FROM
(SELECT * FROM yourTable WHERE id = 1 ORDER BY datetime DESC LIMIT 1) t1
UNION ALL
(SELECT * FROM yourTable WHERE id = 3 ORDER BY datetime DESC LIMIT 1) t2;

Answer 2

select id,
       max(datetime),
       count 
from t1 where id in (1,3)
group by id

** t1是你的表

Answer 3

select * from tablename where id in (1, 3) order by datetime desc limit 2

Answer 4

使用IN，ORDER BY和LIMIT关键字，例如：

SELECT  *
FROM MyTable
WHERE id IN (1, 3)
ORDER BY col2 DESC
LIMIT 2

Answer 5

使用子查询进行内部联接，该子查询返回ID 1和3的最新事务：

Select only
     , the
     , columns
     , you
     , actually 
     , want
FROM myTable tbl
INNER JOIN
(
 SELECT 
 id, 
 MAX(datetime) AS most_recent_tran
 FROM myTable
 WHERE ID in (1,3)
 GROUP BY id
) temp

ON

WHATEVER I JUST CALLED MY COLUMNS

 tbl.ID = temp.ID and tbl.datetime = temp.datetime

选择具有最近日期时间的两个不同的id记录？

5 个答案: