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  • MySQL 日期时间函数大全 （转）

    转载自：http://blog.itpub.net/29773961/viewspace-1808967

    以下内容基于MySQL 5.6及更高，大部分函数5.5也基本适用，更低版本请参考对应版本手册，其内容整理自官方。

    mysql常用函数被分为五类，分别为：

    ①Date and time：日期和时间；

    ②String：字符串函数；
    http://blog.itpub.net/29773961/viewspace-1813545/

    ③Numeric：数字函数；
    http://blog.itpub.net/29773961/viewspace-1813556/

    ④Control Flow：基于一个表达式的结果集选择不同的值（控制流函数）；
    http://blog.itpub.net/29773961/viewspace-1813557/

    ⑤Aggregate：基于一列的多个值返回单一值（聚合函数）；
    http://blog.itpub.net/29773961/viewspace-1813589/

    【Date and time】：

    （补充说明）DATE/TIME 格式：



    NOW()、CURRENT_TIMESTAMP()与CURRENT_TIMESTAMP、LOCALTIME()与LOCALTIME、LOCALTIMESTAMP()与LOCALTIMESTAMP：（均为同义词）
    返回当前的日期和时间，基于Satement（DATETIME格式）

    1. mysql> SELECT NOW(),CURRENT_TIMESTAMP();
    2. +---------------------+---------------------+
    3. | NOW()               | CURRENT_TIMESTAMP() |
    4. +---------------------+---------------------+
    5. | 2015-09-25 14:14:15 | 2015-09-25 14:14:15 |
    6. +---------------------+---------------------+
    7. 1 row in set (0.00 sec)
    1. mysql> SELECT NOW(),LOCALTIME(),LOCALTIME,LOCALTIMESTAMP(),LOCALTIMESTAMP;
    2. +---------------------+---------------------+---------------------+---------------------+---------------------+
    3. | NOW()               | LOCALTIME()         | LOCALTIME           | LOCALTIMESTAMP()    | LOCALTIMESTAMP      |
    4. +---------------------+---------------------+---------------------+---------------------+---------------------+
    5. | 2015-09-25 14:21:23 | 2015-09-25 14:21:23 | 2015-09-25 14:21:23 | 2015-09-25 14:21:23 | 2015-09-25 14:21:23 | 
    6. +---------------------+---------------------+---------------------+---------------------+---------------------+
    7. 1 row in set (0.00 sec)



    SYSDATE()：返回当前的日期和时间，基于系统时间（DATETIME格式）

    1. mysql> mysql> SELECT NOW(),SYSDATE(),SLEEP(1),NOW(),SYSDATE();
    2. +---------------------+---------------------+----------+---------------------+---------------------+
    3. | NOW()               | SYSDATE()           | SLEEP(1) | NOW()               | SYSDATE()           |
    4. +---------------------+---------------------+----------+---------------------+---------------------+
    5. | 2015-09-28 10:49:00 | 2015-09-28 10:49:00 | 0        | 2015-09-28 10:49:00 | 2015-09-28 10:49:01 |
    6. +---------------------+---------------------+----------+---------------------+---------------------+
    7. 1 row in set (1.00 sec)



    CURDATE()与CURRENT_DATE()与CURRENT_DATE：返回当前的日期，基于服务器主机（DATE格式）

    1. mysql> SELECT CURDATE(),CURRENT_DATE();
    2. +------------+----------------+
    3. | CURDATE()  | CURRENT_DATE() |
    4. +------------+----------------+
    5. | 2015-09-25 | 2015-09-25     |
    6. +------------+----------------+
    7. 1 row in set (0.00 sec)



    CURTIME()与CURRENT_TIME()与CURRENT_TIME： 返回当前的时间，基于服务器主机（TIME格式）

    1. mysql> SELECT CURTIME(),CURRENT_TIME();
    2. +-----------+----------------+
    3. | CURTIME() | CURRENT_TIME() |
    4. +-----------+----------------+
    5. | 14:15:19  | 14:15:19       |
    6. +-----------+----------------+
    7. 1 row in set (0.00 sec)



    YEAR()：返回日期的年份（YEAR格式）
    MONTH()：返回日期的月份
    DAY()与DAYOFMONTH()：返回日期的天数
    DAYNAME()：返回星期几

    1. mysql> SELECT YEAR(NOW()),
    2.     -> MONTH(NOW()),
    3.     -> DAY(NOW()),
    4.     -> DAYOFMONTH(NOW()),
    5.     -> DAYNAME(NOW());
    6. +-------------+--------------+------------+-------------------+----------------+
    7. | YEAR(NOW()) | MONTH(NOW()) | DAY(NOW()) | DAYOFMONTH(NOW()) | DAYNAME(NOW()) |
    8. +-------------+--------------+------------+-------------------+----------------+
    9. | 2015        | 9            | 25         | 25                | Friday         |
    10. +-------------+--------------+------------+-------------------+----------------+
    11. 1 row in set (0.00 sec)



    DAYOFWEEK()：返回日期对应的星期，1--周日 2--周一 3--周二 4--周三 5--周四 6--周五 7--周六
    DAYOFYEAR()：返回日期为该年的第多少天

    1. mysql> ! cal
    2.    September 2015 
    3. Su Mo Tu We Th Fr Sa
    4.        1 2 3 4 5
    5.  6 7 8 9 10 11 12
    6. 13 14 15 16 17 18 19
    7. 20 21 22 23 24 25 26
    8. 27 28 29 30
    10. mysql> SELECT DAYOFWEEK(NOW()),
    11.     -> DAYOFYEAR(NOW());
    12. +------------------+------------------+
    13. | DAYOFWEEK(NOW()) | DAYOFYEAR(NOW()) |
    14. +------------------+------------------+
    15. | 2                | 271              |
    16. +------------------+------------------+
    17. 1 row in set (0.00 sec)



    HOUR()：提取时间的小时 
    MINUTE()    ：提取时间的分钟
    SECOND()：提取时间的秒数
    MICROSECOND()：提取时间的微秒

    1. mysql> SELECT HOUR('11:11:12.000123') h,
    2.     -> MINUTE('11:11:12.000123') m,
    3.     -> SECOND('11:11:12.000123') s,
    4.     -> MICROSECOND('11:11:12.000123') ms;
    5. +------+------+------+------+
    6. | h    | m    | s    | ms   |
    7. +------+------+------+------+
    8. | 11   | 11   | 12   | 123  |
    9. +------+------+------+------+
    10. 1 row in set (0.00 sec)



    STR_TO_DATE()：将字符串转换成日期格式（以下三例均可用DATE_FORMAT()替换）

    1. mysql> SELECT STR_TO_DATE('2015-10-31','%Y-%m-%d');
    2. +--------------------------------------+
    3. | STR_TO_DATE('2015-10-31','%Y-%m-%d') |
    4. +--------------------------------------+
    5. | 2015-10-31                           |
    6. +--------------------------------------+
    7. 1 row in set (0.00 sec)
    9. mysql> SELECT STR_TO_DATE('2015-10-31 08:30:59','%Y-%m-%d %H:%i:%s');
    10. +--------------------------------------------------------+
    11. | STR_TO_DATE('2015-10-31 08:30:59','%Y-%m-%d %H:%i:%s') |
    12. +--------------------------------------------------------+
    13. | 2015-10-31 08:30:59                                    |
    14. +--------------------------------------------------------+
    15. 1 row in set (0.00 sec)
    1. mysql> SELECT STR_TO_DATE('20151031083059','%Y%m%d%H%i%s');    -- 格式化的格式要与字符串一致
    2. +----------------------------------------------+
    3. | STR_TO_DATE('20151031083059','%Y%m%d%H%i%s') |
    4. +----------------------------------------------+
    5. | 2015-10-31 08:30:59                          |
    6. +----------------------------------------------+
    7. 1 row in set (0.00 sec)



    DATE_FORMAT()：将日期时间格式化

    1. mysql> SELECT DATE_FORMAT('2015-10-31 08:30:59','%H:%i:%s');    
    2. +-----------------------------------------------+
    3. | DATE_FORMAT('2015-10-31 08:30:59','%H:%i:%s') |
    4. +-----------------------------------------------+
    5. | 08:30:59                                      |
    6. +-----------------------------------------------+
    7. 1 row in set (0.00 sec)
    9. mysql> SELECT DATE_FORMAT(NOW(),'%y/%m/%d');    -- 也可以这样用
    10. +-------------------------------+
    11. | DATE_FORMAT(NOW(),'%y/%m/%d') |
    12. +-------------------------------+
    13. | 15/09/25                      |
    14. +-------------------------------+
    15. 1 row in set (0.00 sec)

    一般情况下，多数场景可用DATE_FORMAT()代替STR_TO_DATE()。


    ADDDATE()：将日期相加减
    DATE_ADD()与DATE_SUB()和SUBDATE()：将日期相加减

    1. mysql> SELECT ADDDATE('2000-01-01',222);
    2. +---------------------------+
    3. | ADDDATE('2000-01-01',222) |
    4. +---------------------------+
    5. | 2000-08-10                |
    6. +---------------------------+
    7. 1 row in set (0.00 sec)
    9. mysql> SELECT ADDDATE('2000-01-01', INTERVAL 111 DAY);
    10. +-----------------------------------------+
    11. | ADDDATE('2000-01-01', INTERVAL 111 DAY) |
    12. +-----------------------------------------+
    13. | 2000-04-21                              |
    14. +-----------------------------------------+
    15. 1 row in set (0.00 sec)
    17. mysql> SELECT DATE_ADD('2000-01-01', INTERVAL 111 DAY);
    18. +------------------------------------------+
    19. | DATE_ADD('2000-01-01', INTERVAL 111 DAY) |
    20. +------------------------------------------+
    21. | 2000-04-21                               |
    22. +------------------------------------------+
    23. 1 row in set (0.00 sec)



    ADDTIME()：将日期与时间相加减

    1. mysql> SELECT ADDTIME('2000-01-01 00:00:01.000000', '1 1:1:1.000001');
    2. +---------------------------------------------------------+
    3. | ADDTIME('2000-01-01 00:00:01.000000', '1 1:1:1.000001') |
    4. +---------------------------------------------------------+
    5. | 2000-01-02 01:01:02.000001                              |
    6. +---------------------------------------------------------+
    7. 1 row in set (0.00 sec)
    9. mysql> SELECT ADDTIME('11:11:11.999999', '1:0:0.000001');
    10. +--------------------------------------------+
    11. | ADDTIME('11:11:11.999999', '1:0:0.000001') |
    12. +--------------------------------------------+
    13. | 12:11:12                                   |
    14. +--------------------------------------------+
    15. 1 row in set (0.00 sec)



    CONVERT_TZ()：转换时区

    1. mysql> SELECT CONVERT_TZ('2000-01-01 12:00:00', '+00:00', '+08:00');    -- 将+0转换为+8
    2. +-------------------------------------------------------+
    3. | CONVERT_TZ('2000-01-01 12:00:00', '+00:00', '+08:00') |
    4. +-------------------------------------------------------+
    5. | 2000-01-01 20:00:00                                   |
    6. +-------------------------------------------------------+
    7. 1 row in set (0.00 sec)



    DATE()：将日期时间转换成日期

    1. mysql> SELECT DATE(NOW());
    2. +-------------+
    3. | DATE(NOW()) |
    4. +-------------+
    5. | 2015-09-28  |
    6. +-------------+
    7. 1 row in set (0.00 sec)



    DATEDIFF()：计算两个日期的差值

    1. mysql> SELECT DATEDIFF(NOW(),'1993-06-12');
    2. +------------------------------+
    3. | DATEDIFF(NOW(),'1993-06-12') |
    4. +------------------------------+
    5. | 8143                         |
    6. +------------------------------+
    7. 1 row in set (0.00 sec)



    额外参数：INTERVAL，用于日期或时间相加（相减），更加灵活。

    1. mysql> SELECT NOW(),
    2.     -> NOW() + INTERVAL 100 DAY,
    3.     -> NOW() - INTERVAL 299 MINUTE;
    4. +---------------------+--------------------------+-----------------------------+
    5. | NOW()               | NOW() + INTERVAL 100 DAY | NOW() - INTERVAL 299 MINUTE |
    6. +---------------------+--------------------------+-----------------------------+
    7. | 2015-09-25 14:39:59 | 2016-01-03 14:39:59      | 2015-09-25 09:40:59         |
    8. +---------------------+--------------------------+-----------------------------+
    9. 1 row in set (0.00 sec)



    EXTRACT()：提取日期时间的部分内容

    1. mysql> SELECT EXTRACT(YEAR FROM '2000-01-02 01:02:03'),
    2.     -> EXTRACT(YEAR_MONTH FROM '2000-01-02 01:02:03'),
    3.     -> EXTRACT(DAY_MINUTE FROM '2000-01-02 01:02:03'),
    4.     -> EXTRACT(MICROSECOND FROM '2000-01-02 01:02:03.000123')G
    5. *************************** 1. row ***************************
    6.               EXTRACT(YEAR FROM '2000-01-02 01:02:03'): 2000
    7.         EXTRACT(YEAR_MONTH FROM '2000-01-02 01:02:03'): 200001
    8.         EXTRACT(DAY_MINUTE FROM '2000-01-02 01:02:03'): 20102
    9. EXTRACT(MICROSECOND FROM '2000-01-02 01:02:03.000123'): 123
    10. 1 row in set (0.00 sec)



    FROM_DAYS()：根据整型数字N（天）返回对应日期

    1. mysql> SELECT FROM_DAYS(366);
    2. +----------------+
    3. | FROM_DAYS(366) |
    4. +----------------+
    5. | 0001-01-01     |
    6. +----------------+
    7. 1 row in set (0.00 sec)
    9. mysql> SELECT FROM_DAYS(735555);
    10. +-------------------+
    11. | FROM_DAYS(735555) |
    12. +-------------------+
    13. | 2013-11-18        |
    14. +-------------------+
    15. 1 row in set (0.00 sec)



    FROM_UNIXTIME()：从UNIX时间戳开始返回经过N秒后的时间

    1. mysql> SELECT FROM_UNIXTIME(0);
    2. +---------------------+
    3. | FROM_UNIXTIME(0)    |
    4. +---------------------+
    5. | 1970-01-01 08:00:00 |
    6. +---------------------+
    7. 1 row in set (0.00 sec)
    9. mysql> SELECT FROM_UNIXTIME(1);
    10. +---------------------+
    11. | FROM_UNIXTIME(1)    |
    12. +---------------------+
    13. | 1970-01-01 08:00:01 |
    14. +---------------------+
    15. 1 row in set (0.00 sec)
    17. mysql> SELECT FROM_UNIXTIME(3600);
    18. +---------------------+
    19. | FROM_UNIXTIME(3600) |
    20. +---------------------+
    21. | 1970-01-01 09:00:00 |
    22. +---------------------+
    23. 1 row in set (0.00 sec)



    GET_FORMAT()：返回格式字符串
    一般在使用DATE_FORMAT时和STR_TO_DATE()时配合。

    1. Function Call                        Result
    2. GET_FORMAT(DATE,'USA')             '%m.%d.%Y'
    3. GET_FORMAT(DATE,'JIS')             '%Y-%m-%d'
    4. GET_FORMAT(DATE,'ISO')             '%Y-%m-%d'
    5. GET_FORMAT(DATE,'EUR')             '%d.%m.%Y'
    6. GET_FORMAT(DATE,'INTERNAL')        '%Y%m%d'
    7. GET_FORMAT(DATETIME,'USA')         '%Y-%m-%d %H.%i.%s'
    8. GET_FORMAT(DATETIME,'JIS')         '%Y-%m-%d %H:%i:%s'
    9. GET_FORMAT(DATETIME,'ISO')         '%Y-%m-%d %H:%i:%s'
    10. GET_FORMAT(DATETIME,'EUR')         '%Y-%m-%d %H.%i.%s'
    11. GET_FORMAT(DATETIME,'INTERNAL')    '%Y%m%d%H%i%s'
    12. GET_FORMAT(TIME,'USA')             '%h:%i:%s %p'
    13. GET_FORMAT(TIME,'JIS')             '%H:%i:%s'
    14. GET_FORMAT(TIME,'ISO')             '%H:%i:%s'
    15. GET_FORMAT(TIME,'EUR')             '%H.%i.%s'
    16. GET_FORMAT(TIME,'INTERNAL')        '%H%i%s'
    1. mysql> SELECT GET_FORMAT(DATE,'USA') a,
    2.     -> STR_TO_DATE('10.31.2003',GET_FORMAT(DATE,'USA')) b,
    3.     -> GET_FORMAT(DATE,'EUR') c,
    4.     -> DATE_FORMAT('2003-10-03',GET_FORMAT(DATE,'EUR')) d;
    5. +----------+------------+----------+------------+
    6. | a        | b          | c        | d          |
    7. +----------+------------+----------+------------+
    8. | %m.%d.%Y | 2003-10-31 | %d.%m.%Y | 03.10.2003 |
    9. +----------+------------+----------+------------+
    10. 1 row in set (0.00 sec)



    LAST_DAY()：返回某个日期的该月最后一天的日期

    1. mysql> SELECT LAST_DAY('2000-02-02'), LAST_DAY('2001-02-03'), LAST_DAY('2000-01-01 00:01:02'), LAST_DAY('2000-00-03'), LAST_DAY('2000-01-33');
    2. +------------------------+------------------------+---------------------------------+------------------------+------------------------+
    3. | LAST_DAY('2000-02-02') | LAST_DAY('2001-02-03') | LAST_DAY('2000-01-01 00:01:02') | LAST_DAY('2000-00-03') | LAST_DAY('2000-01-33')|
    4. +------------------------+------------------------+---------------------------------+------------------------+------------------------+
    5. | 2000-02-29             | 2001-02-28             | 2000-01-31                      | NULL                   | NULL                   |
    6. +------------------------+------------------------+---------------------------------+------------------------+------------------------+
    7. 1 row in set, 2 warnings (0.00 sec)
    9. mysql> SHOW WARNINGS;
    10. +---------+------+----------------------------------------+
    11. | Level   | Code | Message                                |
    12. +---------+------+----------------------------------------+
    13. | Warning | 1292 | Incorrect datetime value: '2000-00-03' |
    14. | Warning | 1292 | Incorrect datetime value: '2000-01-33' |
    15. +---------+------+----------------------------------------+
    16. 2 rows in set (0.00 sec)



    MAKEDATE()：返回某一年的第多少天的具体日期
    MAKETIME()：根据给定参数返回时间（h的上限为838，m的上限为60，s的上限为60，超过上限返回null）

    1. mysql> SELECT MAKEDATE(2000,32) a,
    2.     -> MAKEDATE(2000,366) b,
    3.     -> MAKEDATE(2000,367) c,
    4.     -> MAKEDATE(2000,0) d,
    5.     -> MAKETIME(11,22,30) e,
    6.     -> MAKETIME(25,11,11) f;
    7. +------------+------------+------------+------+----------+----------+
    8. | a          | b          | c          | d    | e        | f        |
    9. +------------+------------+------------+------+----------+----------+
    10. | 2000-02-01 | 2000-12-31 | 2001-01-01 | NULL | 11:22:30 | 25:11:11 |
    11. +------------+------------+------------+------+----------+----------+
    12. 1 row in set (0.00 sec)



    MONTHNAME()：返回月份的名字

    1. mysql> SELECT MONTHNAME(NOW());
    2. +------------------+
    3. | MONTHNAME(NOW()) |
    4. +------------------+
    5. | September        |
    6. +------------------+
    7. 1 row in set (0.00 sec)



    PERIOD_ADD()：增加x个月后并返回，格式是YYM或YYYYMM

    1. mysql> SELECT PERIOD_ADD(200001,5),
    2.     -> PERIOD_ADD(200808,10);
    3. +----------------------+-----------------------+
    4. | PERIOD_ADD(200001,5) | PERIOD_ADD(200808,10) |
    5. +----------------------+-----------------------+
    6. | 200006               | 200906                |
    7. +----------------------+-----------------------+
    8. 1 row in set (0.00 sec)



    PERIOD_DIFF()：返回两个日期相差的月份，格式YYYYMM

    1. mysql> SELECT PERIOD_DIFF(200001,200005), PERIOD_DIFF(199912,199810);
    2. +----------------------------+----------------------------+
    3. | PERIOD_DIFF(200001,200005) | PERIOD_DIFF(199912,199810) |
    4. +----------------------------+----------------------------+
    5. | -4                         | 14                         |
    6. +----------------------------+----------------------------+
    7. 1 row in set (0.00 sec)



    QUARTER()：返回日期的季度，月份1-3为1，4-6为2，7-9为3，10-12为4

    1. mysql> SELECT QUARTER('2015-01-01'), QUARTER('2015-07-01');
    2. +-----------------------+-----------------------+
    3. | QUARTER('2015-01-01') | QUARTER('2015-07-01') |
    4. +-----------------------+-----------------------+
    5. | 1                     | 3                     |
    6. +-----------------------+-----------------------+
    7. 1 row in set (0.00 sec)



    SEC_TO_TIME()：将数字转换成时分秒

    1. mysql> SELECT SEC_TO_TIME(1),
    2.     -> SEC_TO_TIME(1) +0,
    3.     -> SEC_TO_TIME(3600);
    4. +----------------+-------------------+-------------------+
    5. | SEC_TO_TIME(1) | SEC_TO_TIME(1) +0 | SEC_TO_TIME(3600) |
    6. +----------------+-------------------+-------------------+
    7. | 00:00:01       | 1                 | 01:00:00          |
    8. +----------------+-------------------+-------------------+
    9. 1 row in set (0.00 sec)



    SUBTIME()：返回两个时间相减的结果

    1. mysql> SELECT SUBTIME('2000-01-02 23:59:59.000003','2 3:58:58.000002') a, 
    2.     -> SUBTIME('01:02:03.123456','02:02:02.123465') b;
    3. +----------------------------+------------------+
    4. | a                          | b                |
    5. +----------------------------+------------------+
    6. | 1999-12-31 20:01:01.000001 | -00:59:59.000009 |
    7. +----------------------------+------------------+
    8. 1 row in set (0.00 sec)



    TIME_FORMAT()：返回格式化后的日期，若包含小时的部分大于23，%k为小时格式说明符，产生的小时值会模12。

    1. mysql> SELECT TIME_FORMAT('25:00:00', '%H %k %h %I %l'),
    2.     -> TIME_FORMAT('100:00:00', '%H %k %h %i %l');
    3. +-------------------------------------------+--------------------------------------------+
    4. | TIME_FORMAT('25:00:00', '%H %k %h %I %l') | TIME_FORMAT('100:00:00', '%H %k %h %i %l') |
    5. +-------------------------------------------+--------------------------------------------+
    6. | 25 25 01 01 1                             | 100 100 04 00 4                            |
    7. +-------------------------------------------+--------------------------------------------+
    8. 1 row in set (0.00 sec)



    TIME_TO_SEC()：

    1. mysql> SELECT TIME_TO_SEC('23:59:59'), TIME_TO_SEC('00:01:01');
    2. +-------------------------+-------------------------+
    3. | TIME_TO_SEC('23:59:59') | TIME_TO_SEC('00:01:01') |
    4. +-------------------------+-------------------------+
    5. | 86399                   | 61                      |
    6. +-------------------------+-------------------------+
    7. 1 row in set (0.00 sec)



    TIME()：返回时间值

    1. mysql> SELECT NOW(), TIME(NOW());
    2. +---------------------+-------------+
    3. | NOW()               | TIME(NOW()) |
    4. +---------------------+-------------+
    5. | 2015-10-09 15:11:49 | 15:11:49    |
    6. +---------------------+-------------+
    7. 1 row in set (0.00 sec)



    TIMESTAMPADD()：时间戳相加

    1. mysql> SELECT TIMESTAMPADD(MINUTE,1,'2015-01-01 00:59:00') a,
    2.     -> TIMESTAMPADD(WEEK,2,'2000-01-01') b,
    3.     -> TIMESTAMPADD(SECOND,66,'2000-01-01') c;
    4. +---------------------+------------+---------------------+
    5. | a                   | b          | c                   |
    6. +---------------------+------------+---------------------+
    7. | 2015-01-01 01:00:00 | 2000-01-15 | 2000-01-01 00:01:06 |
    8. +---------------------+------------+---------------------+
    9. 1 row in set (0.00 sec)



    TIMESTAMPDIFF()：时间戳相减

    1. mysql> SELECT TIMESTAMPDIFF(MINUTE,'2015-01-01 00:01:00','2015-01-01 00:00:00') a;
    2. +------+
    3. | a    |
    4. +------+
    5. | -1   |
    6. +------+
    7. 1 row in set (0.00 sec)



    TO_DAYS()：返回天数，从0年开始（0000-00-00）

    1. mysql> SELECT TO_DAYS('20000101') a,    -- 这样的写法和'2000-01-01'都可以
    2.     -> TO_DAYS('0000-01-01') b,
    3.     -> TO_DAYS('0000-00-00') c;
    4. +--------+------+------+
    5. | a      | b    | c    |
    6. +--------+------+------+
    7. | 730485 | 1    | NULL |
    8. +--------+------+------+
    9. 1 row in set, 1 warning (0.00 sec)
    11. mysql> SHOW WARNINGS;
    12. +---------+------+----------------------------------------+
    13. | Level   | Code | Message                                |
    14. +---------+------+----------------------------------------+
    15. | Warning | 1292 | Incorrect datetime value: '0000-00-00' |
    16. +---------+------+----------------------------------------+
    17. 1 row in set (0.00 sec)



    TO_SECONDS()：返回秒数，从0年开始（0000-00-00）

    1. mysql> SELECT TO_SECONDS('20000101') a,
    2.     -> TO_SECONDS('00000101') b,
    3.     -> TO_SECONDS('11:11:11') c,
    4.     -> TO_SECONDS('2015-10-09 11:11:11') d;
    5. +-------------+-------+-------------+-------------+
    6. | a           | b     | c           | d           |
    7. +-------------+-------+-------------+-------------+
    8. | 63113904000 | 86400 | 63488188800 | 63611608271 |
    9. +-------------+-------+-------------+-------------+
    10. 1 row in set (0.00 sec)



    UNIX_TIMESTAMP()：

    1. mysql> SELECT UNIX_TIMESTAMP(), UNIX_TIMESTAMP(NOW()), UNIX_TIMESTAMP('1970-01-02 00:00:00');
    2. +------------------+-----------------------+---------------------------------------+
    3. | UNIX_TIMESTAMP() | UNIX_TIMESTAMP(NOW()) | UNIX_TIMESTAMP('1970-01-02 00:00:00') |
    4. +------------------+-----------------------+---------------------------------------+
    5. | 1444376257       | 1444376257            | 57600                                 |
    6. +------------------+-----------------------+---------------------------------------+
    7. 1 row in set (0.00 sec)



    UTC_DATE()：

    1. mysql> SELECT UTC_DATE(), UTC_DATE() + 1;
    2. +------------+----------------+
    3. | UTC_DATE() | UTC_DATE() + 1 |
    4. +------------+----------------+
    5. | 2015-10-09 | 20151010       |
    6. +------------+----------------+
    7. 1 row in set (0.00 sec)



    UTC_TIME()：

    1. mysql> SELECT UTC_TIME(), UTC_TIME() + 60, UTC_TIME + 0;   
    2. +------------+-----------------+--------------+
    3. | UTC_TIME() | UTC_TIME() + 60 | UTC_TIME + 0 |
    4. +------------+-----------------+--------------+
    5. | 07:42:54   | 74314           | 74254        |
    6. +------------+-----------------+--------------+
    7. 1 row in set (0.00 sec)



    UTC_TIMESTAMP()：

    1. mysql> SELECT UTC_TIMESTAMP(), UTC_TIMESTAMP() + 0;
    2. +---------------------+---------------------+
    3. | UTC_TIMESTAMP()     | UTC_TIMESTAMP() + 0 |
    4. +---------------------+---------------------+
    5. | 2015-10-09 07:44:48 | 20151009074448      |
    6. +---------------------+---------------------+
    7. 1 row in set (0.00 sec)



    WEEK()与WEEKOFYEAR()：返回日期是该年的第几个星期（但WEEKOFYEAR()没有模式选择）。
    由于习惯不同，有8种模式。

    ModeFirst day of weekRangeWeek 1 is the first week …
    0 Sunday 0-53 with a Sunday in this year
    1 Monday 0-53 with 4 or more days this year
    2 Sunday 1-53 with a Sunday in this year
    3 Monday 1-53 with 4 or more days this year
    4 Sunday 0-53 with 4 or more days this year
    5 Monday 0-53 with a Monday in this year
    6 Sunday 1-53 with 4 or more days this year
    7 Monday 1-53 with a Monday in this year
    1. mysql> select week('2015-01-08',5);
    2. +----------------------+
    3. | week('2015-01-08',5) |
    4. +----------------------+
    5. | 1                    |
    6. +----------------------+
    7. 1 row in set (0.00 sec)
    9. mysql> select week('2015-01-08',1);
    10. +----------------------+
    11. | week('2015-01-08',1) |
    12. +----------------------+
    13. | 2                    |
    14. +----------------------+
    15. 1 row in set (0.00 sec)



    WEEKDAY()：返回星期的索引；0-周一，1-周二，2-周三，3-周四，4-周五，5-周六，6-周日

    1. mysql> SELECT WEEKDAY('2015-10-09');
    2. +-----------------------+
    3. | WEEKDAY('2015-10-09') |
    4. +-----------------------+
    5. | 4                     |
    6. +-----------------------+
    7. 1 row in set (0.00 sec)



    YEARWEEK()：返回日期是哪一年的第几个星期

      1. mysql> ! cal 1 2015
      2.     January 2015 
      3. Su Mo Tu We Th Fr Sa
      4.              1  2  3
      5.  4  5  6  7  8  9 10
      6. 11 12 13 14 15 16 17
      7. 18 19 20 21 22 23 24
      8. 25 26 27 28 29 30 31
      10. mysql> SELECT YEARWEEK('2015-01-03'), YEARWEEK('2015-01-04');
      11. +------------------------+------------------------+
      12. | YEARWEEK('2015-01-03') | YEARWEEK('2015-01-04') |
      13. +------------------------+------------------------+
      14. | 201452                 | 201501                 |
      15. +------------------------+------------------------+
      16. 1 row in set (0.00 sec)
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  • 原文地址：https://www.cnblogs.com/BobXie85/p/6846092.html
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