MySQL 能够使用MySQL获取列中重复值的计数吗？

可以使用ORDER BY DESC与GROUP BY。让我们首先创建一个表 –

mysql> create table DemoTable
    -> (
    -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,
    -> PostMessage varchar(100)
    -> );
Query OK, 0 rows affected (0.69 sec)

使用插入命令在表中插入一些记录 –

mysql> insert into DemoTable(PostMessage) values('Hi');
Query OK, 1 row affected (0.14 sec)

mysql> insert into DemoTable(PostMessage) values('Hello');
Query OK, 1 row affected (0.16 sec)

mysql> insert into DemoTable(PostMessage) values('Hi');
Query OK, 1 row affected (0.12 sec)

mysql> insert into DemoTable(PostMessage) values('Awesome');
Query OK, 1 row affected (0.18 sec)

mysql> insert into DemoTable(PostMessage) values('Hello');
Query OK, 1 row affected (0.19 sec)

mysql> insert into DemoTable(PostMessage) values('Hi');
Query OK, 1 row affected (0.09 sec)

mysql> insert into DemoTable(PostMessage) values('Awesome');
Query OK, 1 row affected (0.33 sec)

使用select语句从表中显示所有记录-

mysql> select *from DemoTable;

阅读更多：MySQL 教程

输出

这将产生以下输出 –

+----+-------------+
| Id | PostMessage |
+----+-------------+
|  1 | Hi          |
|  2 | Hello       |
|  3 | Hi          |
|  4 | Awesome     |
|  5 | Hello       |
|  6 | Hi          |
|  7 | Awesome     |
+----+-------------+
7 rows in set (0.00 sec)

以下是获取MySQL数据库中值的最高数量的查询 –

mysql> select PostMessage,count(Id) from DemoTable group by PostMessage
    -> order by count(Id) DESC;

输出

这将产生以下输出 –

+-------------+-----------+
| PostMessage | count(Id) |
+-------------+-----------+
| Hi          | 3         |
| Hello       | 2         |
| Awesome     | 2         |
+-------------+-----------+
3 rows in set (0.00 sec)

如果您只想要最高值，可以使用以下查询 –

mysql> select PostMessage,count(Id)  from DemoTable group by PostMessage having count(Id) > 2;

输出

这将产生以下输出 –

+-------------+-----------+
| PostMessage | count(Id) |
+-------------+-----------+
| Hi          | 3         |
+-------------+-----------+
1 row in set (0.00 sec)