让我们首先创建一个表-
mysql> create table DemoTable ( AdmissionDate datetime );
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable values('2010-01-10 12:30:45'); mysql> insert into DemoTable values('2010-01-10 12:30:45'); mysql> insert into DemoTable values('2010-01-10 12:30:45'); mysql> insert into DemoTable values('2010-01-12 12:30:45'); mysql> insert into DemoTable values('2010-01-20 12:30:45'); mysql> insert into DemoTable values('2010-01-20 12:30:45');
使用select语句显示表中的所有记录-
mysql> select *from DemoTable;
这将产生以下输出-
+---------------------+ | AdmissionDate | +---------------------+ | 2010-01-10 12:30:45 | | 2010-01-10 12:30:45 | | 2010-01-10 12:30:45 | | 2010-01-12 12:30:45 | | 2010-01-20 12:30:45 | | 2010-01-20 12:30:45 | +---------------------+ 6 rows in set (0.00 sec)
以下是显示不同日期的查询-
mysql> select distinct AdmissionDate from DemoTable;
这将产生以下输出-
+---------------------+ | AdmissionDate | +---------------------+ | 2010-01-10 12:30:45 | | 2010-01-12 12:30:45 | | 2010-01-20 12:30:45 | +---------------------+ 3 rows in set (0.00 sec)