【Mysql】时间处理

mysql时间处理

通常我们会有一些时间的转换需求，比如要统计某个时间段的收入，比如要截取某个时间的年份，比如要根据某个日期推算出是星期几等个，这些都可以通过Mysql自带的时间函数很容易实现。因为我对Mysql的函数还不熟，而通常又会调用这些时间函数，这边稍加总结以便查询。

–返回当前时间

mysql> select now(),date(now()),sysdate();

+---------------------+-------------+---------------------+

| now() | date(now()) | sysdate() |
+---------------------+-------------+---------------------+
| 2008-12-02 10:11:36 | 2008-12-02 | 2008-12-02 10:11:36 |
+---------------------+-------------+---------------------+
1 row in set (0.00 sec)

mysql> select curdate(),curdate()+0,curtime(),curtime()+0; 

+---------------------+-------------+---------------------+

| curdate() | curdate()+0 | curtime() | curtime()+0 |
+---------------------+-------------+---------------------+
| 2008-12-02 | 20081202 | 10:00:33 | 100033.000000 |
+---------------------+-------------+---------------------+

–返回日期当月最后一天

mysql> select last_day(‘2008-12-02‘);

+------------------------+

| last_day(‘2008-12-02‘) |
+------------------------+
| 2008-12-31 |
+------------------------+
1 row in set (0.00 sec)

–返回日期的星期几

mysql> select dayname(‘2008-12-02‘),dayofweek(‘2008-12-02‘);

+-----------------------+-------------------------+
| dayname(‘2008-12-02‘) | dayofweek(‘2008-12-02‘) |
+-----------------------+-------------------------+
| tuesday | 3 |
+-----------------------+-------------------------+
1 row in set (0.00 sec)

–返回日期的年，月，日

mysql> select month(‘2008-12-02‘),year(‘2008-12-02‘),day(‘2008-12-02‘);

+---------------------+--------------------+-------------------+

| month(‘2008-12-02‘) | year(‘2008-12-02‘) | day(‘2008-12-02‘) |
+---------------------+--------------------+-------------------+
| 12 | 2008 | 2 |
+---------------------+--------------------+-------------------+
1 row in set (0.00 sec)

–返回日期的小时，分，秒

mysql> select hour(‘10:05:03‘),minute(‘10:05:03‘),second(‘10:05:03‘); 

+------------------+--------------------+--------------------+

| hour(‘10:05:03‘) | minute(‘10:05:03‘) | second(‘10:05:03‘) |
+------------------+--------------------+--------------------+
| 10 | 5 | 3 |
+------------------+--------------------+--------------------+
1 row in set (0.00 sec)

1.subdate(d,t)：起始时间加上一段时间（year,month,day…）

mysql> select date_add(‘1998-01-02‘, interval 31 day),adddate(‘1998-01-02‘, 31); 

+-----------------------------------------+---------------------------+
| date_add(‘1998-01-02‘, interval 31 day) | adddate(‘1998-01-02‘, 31) |
+-----------------------------------------+---------------------------+
| 1998-02-02 | 1998-02-02 |
+-----------------------------------------+---------------------------+
1 row in set (0.00 sec)

mysql> select date_add(‘1998-01-02‘,interval 2 year);

+-----------------------------------------------------+
| date_add(‘1998-01-02‘, interval 2 year)
+-----------------------------------------------------+
| 2000-01-02
+-----------------------------------------------------+
1 row in set (0.00 sec)

mysql> select date_add(‘1998-01-02‘, interval 2 hour);

+-----------------------------------------------------+
| date_add(‘1998-01-02‘, interval 2 hour)
+-----------------------------------------------------+
| 1998-01-02 02:00:00
+-----------------------------------------------------+
1 row in set (0.00 sec)

2.subdate(d,t)：起始时间减去一段时间

mysql> select subdate(‘1998-01-02‘, interval 31 day),subdate(‘1998-01-02‘, 31);

+----------------------------------------+---------------------------+
| subdate(‘1998-01-02‘, interval 31 day) | subdate(‘1998-01-02‘, 31) |
+----------------------------------------+---------------------------+
| 1997-12-02 | 1997-12-02 |
+----------------------------------------+---------------------------+
1 row in set (0.00 sec)

3.addtime(d,t):起始时间d加入时间t

mysql> select addtime(‘1997-12-31 23:59:50‘,‘00:00:05‘), addtime(‘23:59:50‘,‘00:00:05‘) ;

+-------------------------------------------+--------------------------------+
| addtime(‘1997-12-31 23:59:50‘,‘00:00:05‘) | addtime(‘23:59:50‘,‘00:00:05‘) |
+-------------------------------------------+--------------------------------+
| 1997-12-31 23:59:55 | 23:59:55 |
+-------------------------------------------+--------------------------------+
1 row in set (0.00 sec)

4.subtime(d,t):起始时间d减去时间t

mysql> select subtime(‘1997-12-31 23:59:50‘,‘00:00:05‘), subtime(‘23:59:50‘,‘00:00:05‘); 

+-------------------------------------------+--------------------------------+
| subtime(‘1997-12-31 23:59:50‘,‘00:00:05‘) | subtime(‘23:59:50‘,‘00:00:05‘) |
+-------------------------------------------+--------------------------------+
| 1997-12-31 23:59:45 | 23:59:45 |
+-------------------------------------------+--------------------------------+
1 row in set (0.00 sec)

5.datediff(d1,d2):返回起始时间d1和结束时间d2之间的天数

mysql> select datediff(‘1997-12-31 23:59:59‘,‘1997-12-30‘);

+----------------------------------------------+
| datediff(‘1997-12-31 23:59:59‘,‘1997-12-30‘) |
+----------------------------------------------+
| 1 |
+----------------------------------------------+
1 row in set (0.00 sec)

6.date_format(date,format):根据format字符串显示date值的格式

mysql> select date_format(‘2008-12-02 22:23:00‘, ‘%y %m %m %h:%i:%s‘);

+---------------------------------------------------------+
| date_format(‘2008-12-02 22:23:00‘, ‘%y %m %m %h:%i:%s‘) |
+---------------------------------------------------------+
| 2008 12 12 22:23:00 |
+---------------------------------------------------------+
1 row in set (0.00 sec)

7.str_to_date(str,format) 字符串转化为时间

mysql> select str_to_date(‘04/31/2004‘, ‘%m/%d/%y %h:%i:s‘);

+-----------------------------------------------+
| str_to_date(‘04/31/2004‘, ‘%m/%d/%y %h:%i:s‘) |
+-----------------------------------------------+
| 2004-04-31 00:00:00 |
+-----------------------------------------------+
1 row in set (0.00 sec)

8.timestamp(expr) , timestamp(expr,expr2) :
对于一个单参数,该函数将日期或日期时间表达式 expr 作为日期时间值返回.对于两个参数, 它将时间表达式 expr2添加到日期或日期时间表达式 expr 中，将theresult作为日期时间值返回

mysql> select timestamp(‘2003-12-31‘), timestamp(‘2003-12-31 12:00:00‘,‘12:00:00‘);

+-------------------------+---------------------------------------------+
| timestamp(‘2003-12-31‘) | timestamp(‘2003-12-31 12:00:00‘,‘12:00:00‘) |
+-------------------------+---------------------------------------------+
| 2003-12-31 00:00:00 | 2004-01-01 00:00:00 |
+-------------------------+---------------------------------------------+
1 row in set (0.00 sec)

9.取当天0点0分，下一天0点0分

mysql> select timestamp(date(sysdate())),timestamp(adddate(date(sysdate()),1)); 

+----------------------------+---------------------------------------+
| timestamp(date(sysdate())) | timestamp(adddate(date(sysdate()),1)) |
+----------------------------+---------------------------------------+
| 2008-12-02 00:00:00 | 2008-12-03 00:00:00 |
+----------------------------+---------------------------------------+
1 row in set (0.00 sec)