时间函数对应mysql版本5.7,低版本未测
1、获取当前日期的函数，返回格式"YYYY-MM-DD"
mysql> select curdate(),current_date();
+------------+----------------+
| curdate() | current_date() |
+------------+----------------+
| 2019-10-30 | 2019-10-30 |
+------------+----------------+
1 row in set (0.05 sec)2、获取当前日期的函数，返回格式"YYYY-MM-DD HH:MM:SS"
mysql> select now(),sysdate(),current_timestamp(),localtime();
+---------------------+---------------------+---------------------+---------------------+
| now() | sysdate() | current_timestamp() | localtime() |
+---------------------+---------------------+---------------------+---------------------+
| 2019-10-30 14:03:46 | 2019-10-30 14:03:46 | 2019-10-30 14:03:46 | 2019-10-30 14:03:46 |
+---------------------+---------------------+---------------------+---------------------+
1 row in set (0.11 sec)3、UNIX时间戳函数
mysql> select unix_timestamp(),unix_timestamp(now()),now();
+------------------+-----------------------+---------------------+
| unix_timestamp() | unix_timestamp(now()) | now() |
+------------------+-----------------------+---------------------+
| 1572418048 | 1572418048 | 2019-10-30 14:47:28 |
+------------------+-----------------------+---------------------+
1 row in set (0.11 sec)from_unixtime与unix_timestamp为互反函数
mysql> select from_unixtime(1572418048);
+---------------------------+
| from_unixtime(1572418048) |
+---------------------------+
| 2019-10-30 14:47:28 |
+---------------------------+
1 row in set (0.10 sec)4、返回UTC日期和时间的函数
mysql> select utc_date(),utc_time();
+------------+------------+
| utc_date() | utc_time() |
+------------+------------+
| 2019-10-30 | 06:56:44 |
+------------+------------+
1 row in set (0.09 sec)5、获取月份的函数
MONTH(date)函数返回对应的月份，MONTHNAME(date)返回月份对应的英文
mysql> select month('2019-10-30'),monthname('2019-10-30');
+---------------------+-------------------------+
| month('2019-10-30') | monthname('2019-10-30') |
+---------------------+-------------------------+
| 10 | October |
+---------------------+-------------------------+
1 row in set (0.09 sec)6、获取星期的函数
dayname(d)函数返回d对应的工作日的英文名称
dayofweek(d)返回日期所在周的索引
mysql> select dayname('2019-10-30'),dayofweek('2019-10-30');
+-----------------------+-------------------------+
| dayname('2019-10-30') | dayofweek('2019-10-30') |
+-----------------------+-------------------------+
| Wednesday | 4 |
+-----------------------+-------------------------+
1 row in set (0.10 sec)7、获取星期数的函数
week(d,default_week_format)默认值是0，指定一周的第一天为周日，1则指定一周的第一天为周一
weekofyear(d)某天位于一年中的第几周，相当于week(d,3)
mysql> select week('2019-10-30'),weekofyear('2019-10-30');
+--------------------+--------------------------+
| week('2019-10-30') | weekofyear('2019-10-30') |
+--------------------+--------------------------+
| 43 | 44 |
+--------------------+--------------------------+
1 row in set (0.13 sec)
mysql> select week('2019-10-30',1),weekofyear('2019-10-30');
+----------------------+--------------------------+
| week('2019-10-30',1) | weekofyear('2019-10-30') |
+----------------------+--------------------------+
| 44 | 44 |
+----------------------+--------------------------+
1 row in set (0.09 sec)8、获取天数的函数
dayofyear(d) 一年中的第几天
dayofmonth(d)一个月中的第几天
mysql> select dayofmonth('2019-10-30'),dayofyear('2019-10-30');
+--------------------------+-------------------------+
| dayofmonth('2019-10-30') | dayofyear('2019-10-30') |
+--------------------------+-------------------------+
| 30 | 303 |
+--------------------------+-------------------------+
1 row in set (0.09 sec)9、获取年份、季度、小时、分钟和秒钟的函数
mysql> select year('2019-10-30 14:47:28'),quarter('2019-10-30 14:47:28'),minute('2019-10-30 14:47:28'),second('2019-10-30 14:47:28');
+-----------------------------+--------------------------------+-------------------------------+-------------------------------+
| year('2019-10-30 14:47:28') | quarter('2019-10-30 14:47:28') | minute('2019-10-30 14:47:28') | second('2019-10-30 14:47:28') |
+-----------------------------+--------------------------------+-------------------------------+-------------------------------+
| 2019 | 4 | 47 | 28 |
+-----------------------------+--------------------------------+-------------------------------+-------------------------------+
1 row in set (0.11 sec)10、时间和秒钟转换的函数
time_to_sec(time)
sec_to_time(second)
mysql> select time_to_sec('14:47:28'),sec_to_time(53248);
+-------------------------+--------------------+
| time_to_sec('14:47:28') | sec_to_time(53248) |
+-------------------------+--------------------+
| 53248 | 14:47:28 |
+-------------------------+--------------------+
1 row in set (0.10 sec)11、计算日期和时间的函数
date_add(date,interval expr type)
adddate(date,interval expr type)
date_sub(date,interval expr type)
subdate(date,interval expr type)
addtime(date,expr)
subtime(date,expr)
datediff() 两个日期的间隔天数
| type值 | 预期的expr格式 |
|---|---|
| MICROSECOND | MICROSECONDS |
| SECOND | SECONDS |
| MINUTE | MINUTES |
| HOUR |
HOURS |
| DAY | DAYS |
| WEEK | WEEKS |
| MONTH | MONTHS |
| QUARTER | QUARTERS |
| YEAR | YEARS |
| SECOND_MICROSECOND |
'SECONDS.MICROSECONDS' |
| MINUTE_MICROSECOND | 'MINUTES.MICROSECONDS' |
| MINUTE_SECOND | 'MINUTES:SECONDS' |
| HOUR_MICROSECOND | 'HOUR.MICROSECONDS' |
| HOUR_SECOND | 'HOURS:MINUTES:SECONDS' |
| HOUR_MINUTE | 'HOURS:MINUTES' |
| DAY_MICROSECOND | 'DAYS:MICROSECONDS' |
| DAY_SECOND | 'DAYS HOURS:MINUTES:SECONDS' |
| DAY_MINUTE | 'DAYS HOURS:MINUTES' |
| DAY_HOUR | 'DAYS HOURS' |
| YEAR_MONTH | 'YEARS-MONTHS' |
举例：使用三个type值 day,second,year_month 其他类比
mysql> select date_sub('2019-10-30',interval 10 day),date_sub('2019-10-30 14:47:28',interval 10 second),date_add('2019-10-30 14:47:28',interval '1_1' year_month);
+----------------------------------------+----------------------------------------------------+-----------------------------------------------------------+
| date_sub('2019-10-30',interval 10 day) | date_sub('2019-10-30 14:47:28',interval 10 second) | date_add('2019-10-30 14:47:28',interval '1_1' year_month) |
+----------------------------------------+----------------------------------------------------+-----------------------------------------------------------+
| 2019-10-20 | 2019-10-30 14:47:18 | 2020-11-30 14:47:28 |
+----------------------------------------+----------------------------------------------------+-----------------------------------------------------------+addtime
mysql> select addtime('2019-10-30 14:47:28','1:1:1'),addtime('14:47:28','1:1:1');
+----------------------------------------+-----------------------------+
| addtime('2019-10-30 14:47:28','1:1:1') | addtime('14:47:28','1:1:1') |
+----------------------------------------+-----------------------------+
| 2019-10-30 15:48:29 | 15:48:29 |
+----------------------------------------+-----------------------------+
1 row in set (0.09 sec)datediff
mysql> select datediff('2019-10-30 14:47:28','2019-09-23 10:27:18');
+-------------------------------------------------------+
| datediff('2019-10-30 14:47:28','2019-09-23 10:27:18') |
+-------------------------------------------------------+
| 37 |
+-------------------------------------------------------+
1 row in set (0.10 sec)12、将日期时间格式化的函数
date_format(date,format)
| 说明符 | 说明 |
|---|---|
| %a | 工作日的缩写名称（Sun...Sat） |
| %b | 月份的缩写名称（Jan...Dec） |
| %c | 月份、数字形式 |
| %D | 带有英语后缀的该月日期 |
| %d | 该月日期，数字形式 |
| %e | 该月日期，数字形式 |
| %f | 微妙 |
| %H | 以2位数表示24小时 |
| %h | 以2位数表示12小时 |
| %i | 分钟，数字形式 |
| %j | 一年中的天数 |
| %k | 以24小时表示时间 |
| %l | 以12小时表示时间 |
| %M | 月份名称，英文 |
| %m | 月份名称，数字形式 |
| %p | 上午AM 或者下午PM |
| %r | 时间12小时制 |
| %S,%s | 以数字形式表示秒 |
| %W | 工作日名称，中文 |
| %w | 一周的工作日，0表示周日 |
| %Y | 四位数表示年份 |
| %y | 两位数表示年份 |
| %% | ‘%’文字字符 |
mysql> select date_format('2019-10-30 14:47:28','%a %b %c %d %M %m %Y %y');
+--------------------------------------------------------------+
| date_format('2019-10-30 14:47:28','%a %b %c %d %M %m %Y %y') |
+--------------------------------------------------------------+
| Wed Oct 10 30 October 10 2019 19 |
+--------------------------------------------------------------+
1 row in set (0.08 sec)