SQL时间段查询(二)
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 |