日期函数

日期和时间函数

1>获取当前日期的函数:CURDATE(),CURRENT_DATE(),CURDATE()+0

mysql> SELECT CURDATE(),CURRENT_DATE(),CURDATE()+0;
+------------+----------------+-------------+
| CURDATE()  | CURRENT_DATE() | CURDATE()+0 |
+------------+----------------+-------------+
| 2017-07-31 | 2017-07-31     |    20170731 |
+------------+----------------+-------------+
1 row in set (0.03 sec)

获取当前时间的函数CURTIME(),CURRENT_TIME()

mysql> SELECT CURRENT_time(),curtime();
+----------------+-----------+
| CURRENT_time() | curtime() |
+----------------+-----------+
| 16:54:19       | 16:54:19  |
+----------------+-----------+
1 row in set (0.00 sec)

获取当前日期和时间的函数:CURRENT_TIMESTAMP(),LOCALTIME(),NOW(),SYSDATE()

mysql> SELECT CURRENT_TIMESTAMP(),LOCALTIME(),NOW(),SYSDATE();
+---------------------+---------------------+---------------------+-------------
--------+
| CURRENT_TIMESTAMP() | LOCALTIME()         | NOW()               | SYSDATE()
    |
+---------------------+---------------------+---------------------+-------------
--------+
| 2017-07-31 16:51:57 | 2017-07-31 16:51:57 | 2017-07-31 16:51:57 | 2017-07-31 1
6:51:57 |
+---------------------+---------------------+---------------------+-------------
--------+
1 row in set (0.04 sec)

2>返回UTC日期的函数UTC_DATE()

mysql> SELECT UTC_DATE();
+------------+
| UTC_DATE() |
+------------+
| 2017-07-31 |
+------------+
1 row in set (0.00 sec)

返回UTC时间的函数UTC_TIME()

mysql> SELECT UTC_TIME();
+------------+
| UTC_TIME() |
+------------+
| 08:58:54   |
+------------+
1 row in set (0.00 sec)

3>获取月份的函数MONTH(date)和MONTHNAME(date)

mysql> select month('2017-5-18'),monthname('2017-5-18');
+--------------------+------------------------+
| month('2017-5-18') | monthname('2017-5-18') |
+--------------------+------------------------+
|                  5 | May                    |
+--------------------+------------------------+
1 row in set (0.02 sec)

4>获取星期的函数DAYNAME(d)、DAYOFWEEK(d)、WEEKDAY(d)

mysql> select dayname('2017-7-31'),dayofweek('2017-7-31'),weekday('2017-7-31');
+----------------------+------------------------+----------------------+
| dayname('2017-7-31') | dayofweek('2017-7-31') | weekday('2017-7-31') |
+----------------------+------------------------+----------------------+
| Monday               |                      2 |                    0 |
+----------------------+------------------------+----------------------+
1 row in set (0.10 sec)

5>获取星期数的函数WEEK(d)和WEEKOFYEAR(d)

mysql> select week('2017-02-20',1),weekofyear('2017-02-20');
+----------------------+--------------- -----------+
| week('2017-02-20',1) | weekofyear('2017-02-20') |
+----------------------+--------------------------+
|                    8 |                        8 |
+----------------------+--------------------------+
1 row in set (0.00 sec)

6>获取天数的函数DAYOFYEAR(d)和DAYOFMONTH(d)

mysql> select dayofyear('2017-02-20'),dayofmonth('2017-07-30');
+-------------------------+--------------------------+
| dayofyear('2017-02-20') | dayofmonth('2017-07-30') |
+-------------------------+--------------------------+
|                      51 |                       30 |
+-------------------------+--------------------------+
1 row in set (0.04 sec)

7>获取年份、季度、小时、分钟、秒钟的函数

mysql> select year('2017-7-31'),quarter('17-7-31'),minute('17-7-31 17:23:13'),se
cond('10:03:50');
+-------------------+--------------------+----------------------------+---------
-----------+
| year('2017-7-31') | quarter('17-7-31') | minute('17-7-31 17:23:13') | second('
10:03:50') |
+-------------------+--------------------+----------------------------+---------
-----------+
|              2017 |                  3 |                         23 |
        50 |
+-------------------+--------------------+----------------------------+---------
-----------+
1 row in set (0.00 sec)

8>获取如期指定值的函数EXTRACT(type FROM date)

mysql> select extract(year from '2017-04-15');
+---------------------------------+
| extract(year from '2017-04-15') |
+---------------------------------+
|                            2017 |
+---------------------------------+
1 row in set (0.17 sec)

mysql> select extract(year_month from '2017-04-15');
+---------------------------------------+
| extract(year_month from '2017-04-15') |
+---------------------------------------+
|                                201704 |
+---------------------------------------+
1 row in set (0.00 sec)

9>时钟和秒钟转换的函数

mysql> select time_to_sec('23:23:00');
+-------------------------+
| time_to_sec('23:23:00') |
+-------------------------+
|                   84180 |
+-------------------------+
1 row in set (0.00 sec)


mysql> select sec_to_time(84180);
+--------------------+
| sec_to_time(84180) |
    +--------------------+
| 23:23:00           |
+--------------------+
1 row in set (0.02 sec)

10>计算日期和时间的函数

mysql> SELECT date_add('2017-12-31 23:59:59', interval 1 second);
+----------------------------------------------------+
| date_add('2017-12-31 23:59:59', interval 1 second) |
+----------------------------------------------------+
| 2018-01-01 00:00:00                                |
+----------------------------------------------------+
1 row in set (0.05 sec)

mysql> SELECT date_add('2017-12-31 23:59:59', interval '1:1' minute_second);
+---------------------------------------------------------------+
| date_add('2017-12-31 23:59:59', interval '1:1' minute_second) |
+---------------------------------------------------------------+
| 2018-01-01 00:01:00                                           |
+---------------------------------------------------------------+
1 row in set (0.00 sec)

mysql> SELECT adddate('2017-12-31 23:59:59', interval '1:1' minute_second);
+--------------------------------------------------------------+
| adddate('2017-12-31 23:59:59', interval '1:1' minute_second) |
+--------------------------------------------------------------+
| 2018-01-01 00:01:00                                          |
+--------------------------------------------------------------+
1 row in set (0.02 sec)

---

mysql> select date_sub('2017-7-31 00:01:00',interval '0 0:1:1' day_second);
+--------------------------------------------------------------+
| date_sub('2017-7-31 00:01:00',interval '0 0:1:1' day_second) |
+--------------------------------------------------------------+
| 2017-07-30 23:59:59                                        |
+--------------------------------------------------------------+
1 row in set (0.00 sec)

mysql> select date_sub('2017-7-31',interval 30 day);    
+---------------------------------------+
| date_sub('2017-7-31',interval 30 day) |
+---------------------------------------+
| 2017-07-01                            |
+---------------------------------------+
1 row in set (0.00 sec)

mysql> select subdate('2017-7-31',interval 30 day);
+--------------------------------------+
| subdate('2017-7-31',interval 30 day) |
+--------------------------------------+
| 2017-07-01                           |
+--------------------------------------+
1 row in set (0.00 sec)

---

mysql> select addtime('2017-7-31 4:4:4','1:1:1');
+------------------------------------+
| addtime('2017-7-31 4:4:4','1:1:1') |
+------------------------------------+
| 2017-07-31 05:05:05                |
+------------------------------------+
1 row in set (0.04 sec)

mysql> select subtime('2017-7-31 4:4:4','1:1:1');
+------------------------------------+
| subtime('2017-7-31 4:4:4','1:1:1') |
+------------------------------------+
| 2017-07-31 03:03:03                |
+------------------------------------+
1 row in set (0.01 sec)

mysql> select datediff('2017-7-30 2:2:2','2017-7-28');
+-----------------------------------------+
| datediff('2017-7-30 2:2:2','2017-7-28') |
+-----------------------------------------+
|                                       2 |
+-----------------------------------------+
1 row in set (0.04 sec)

11>将日期和时间格式化的函数

DATE_FORMAT()函数格式化输出日期和时间值。

mysql> select date_format('2017-7-30 12:00:00','%w %m %y');
+----------------------------------------------+
| date_format('2017-7-30 12:00:00','%w %m %y') |
+----------------------------------------------+
| 0 07 17                                      |
+----------------------------------------------+
1 row in set (0.00 sec)



mysql> select time_format('9:02:10','%H %k %h %I %l');
+-----------------------------------------+
| time_format('9:02:10','%H %k %h %I %l') |
+-----------------------------------------+
| 09 9 09 09 9                            |
+-----------------------------------------+
1 row in set (0.00 sec)



mysql> select get_format(date,'EUR');
+------------------------+
| get_format(date,'EUR') |
+------------------------+
| %d.%m.%Y               |
+------------------------+
1 row in set (0.00 sec)