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Mysql 如何根据日期进行记录_Mysql_Sql - Fatal编程技术网

Mysql 如何根据日期进行记录

Mysql 如何根据日期进行记录,mysql,sql,Mysql,Sql,在我的数据表中,有一个名为special\u id的列,其中包含非唯一的值 例如: +-----+-----+------------+-------------------------+ | ... | ... | special_id | add_date | +-----+-----+------------+-------------------------+ | ... | ... | 1111 | 2018-02-02 09:42:11.99

在我的数据表中,有一个名为
special\u id
的列,其中包含非唯一的值

例如:

+-----+-----+------------+-------------------------+
| ... | ... | special_id |        add_date         |
+-----+-----+------------+-------------------------+
| ... | ... |       1111 | 2018-02-02 09:42:11.993 |
| ... | ... |       2222 | 2018-02-01 09:42:11.993 |
| ... | ... |       1111 | 2018-01-31 09:42:11.993 |
| ... | ... |       3333 | 2018-01-02 09:42:11.993 |
| ... | ... |       4444 | 2018-01-22 09:42:11.993 |
+-----+-----+------------+-------------------------+
我想知道我是否可以(使用SQL)
根据
add\u date
列选择
最新的记录,并匹配
特殊id

select t.*
from t
where t.add_date = (select max(t2.add_date) from t t2 where t2.special_id = t.special_id);
这就是你的意思吗

select t.*
from t
where t.add_date = (select max(t2.add_date) from t t2 where t2.special_id = t.special_id);

我想这可以奏效

SELECT special_id, MAX(add_date)
FROM test_tbl
GROUP BY special_id;

我想这可以奏效

SELECT special_id, MAX(add_date)
FROM test_tbl
GROUP BY special_id;

如果你只对第一张唱片感兴趣,那么LIMIT会帮你的。所以你可以试试

SELECT *
FROM t
ORDER BY add_date DESC
LIMIT 1;

如果你只对第一张唱片感兴趣,那么LIMIT会帮你的。所以你可以试试

SELECT *
FROM t
ORDER BY add_date DESC
LIMIT 1;