MySQL 使用MySQL获取当前日期注册的人数

为此，您可以使用COUNT()和GROUP BY MONTH()。要与当前日期匹配，请使用CURRENT_DATE()。当前日期如下 –

mysql> select curdate() ;
+------------+
| curdate() |
+------------+
| 2019-11-30 |
+------------+
1 row in set (0.00 sec)

让我们首先创建一个表 –

mysql> create table DemoTable1819
(
Name varchar(20),
RegisteringDate datetime
);
Query OK, 0 rows affected (0.00 sec)

使用insert命令在表中插入一些记录 –

mysql> insert into DemoTable1819 values('Chris','2019-11-29 12:30:34');
Query OK, 1 row affected (0.00 sec)
mysql> insert into DemoTable1819 values('David','2019-11-30 12:30:34');
Query OK, 1 row affected (0.00 sec)
mysql> insert into DemoTable1819 values('Mike','2019-12-30 12:30:34');
Query OK, 1 row affected (0.00 sec)
mysql> insert into DemoTable1819 values('Sam','2018-11-30 11:00:00');
Query OK, 1 row affected (0.00 sec)
mysql> insert into DemoTable1819 values('Carol','2019-11-30 10:00:00');
Query OK, 1 row affected (0.00 sec)

使用select语句从表中显示所有记录 –

mysql> select * from DemoTable1819;

这将产生以下输出 –

+-------+---------------------+
| Name | RegisteringDate |
+-------+---------------------+
| Chris | 2019-11-29 12:30:34 |
| David | 2019-11-30 12:30:34 |
| Mike | 2019-12-30 12:30:34 |
| Sam | 2018-11-30 11:00:00 |
| Carol | 2019-11-30 10:00:00 |
+-------+---------------------+
5 rows in set (0.00 sec)

下面是检索当前日期注册的人数的查询 –

mysql> select count(RegisteringDate) as Output from DemoTable1819 WHERE DATE(RegisteringDate) = CURDATE() GROUP BY MONTH(RegisteringDate);

这将产生以下输出 –

+--------+
| Output |
+--------+
| 2 |
+--------+
1 row in set (0.00 sec)

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