Example of using MySQL date function
Date function
1. CURDATE()/CURRENT_DATE() returns the current date
SELECT CURDATE(); SELECT CURRENT_DATE(); ---- 返回2019-02-19
2. CURRENT_TIME() /CURTIME() returns the current time
SELECT CURRENT_TIME(); ---- 返回11:40:45
3, CURRENT_TIMESTAMP() returns the current date and time
SELECT CURRENT_TIMESTAMP(); ---- 返回2019-02-19 11:41:32
4, ADDDATE(d,n ) Calculate the starting date d plus n days of date
SELECT ADDDATE("2017-06-15", INTERVAL 10 DAY); ---- 返回2017-06-25
5. ADDTIME(t,n) time t plus n seconds of time
SELECT ADDTIME('2011-11-11 11:11:11', 5); ---- 返回2011-11-11 11:11:16
6. DATE() extracts the date value from the date or datetime expression
SELECT DATE("2017-06-15 11:11:16"); ---- 返回2017-06-15
7. DAY(d) returns the date part of the date value d
SELECT DAY("2017-06-15"); ---- 返回15
8. DATEDIFF(d1,d2) calculates the number of days between dates d1->d2
SELECT DATEDIFF('2001-01-01','2001-02-02'); ---- 返回-32
9. DATE_FORMAT according to expression f It is required to display date d
SELECT DATE_FORMAT('2011.11.11 11:11:11','%Y-%m-%d %r'); ---- 返回2011-11-11 11:11:11 AM
10, DAYNAME(d) and return date d which is the day of the week, such as Monday, Tuesday
SELECT DAYNAME('2011-11-11 11:11:11'); ---- 返回Friday
11, DAYOFMONTH( d) Calculate the day of the month that date d is
SELECT DAYOFMONTH('2011-11-11 11:11:11'); ---- 返回11
12. DAYOFWEEK(d) Date d is the day of the week today, 1 is Sunday, 2 is Monday, and so on
SELECT DAYOFWEEK('2011-11-11 11:11:11'); ---- 返回6
13. DAYOFYEAR(d) calculates the day of the year when date d is
SELECT DAYOFYEAR('2011-11-11 11:11:11'); ---- 返回315
14. EXTRACT(type FROM d) from date Get the specified value in d, type specifies the returned value
The possible values of type are:
MICROSECOND
SECOND
MINUTE
HOUR
DAY
WEEK
MONTH
QUARTER
YEAR
SECOND_MICROSECOND
MINUTE_MICROSECOND
MINUTE_SECOND
HOUR_MICROSECOND
HOUR_SECOND
HOUR_MINUTE
DAY_MICROSECOND
DAY_SECOND
DAY_MINUTE
DAY_HOUR
YEAR_MONTH
SELECT EXTRACT(MINUTE FROM '2011-12-13 14:15:16'); ---- 返回15
15. DAYOFWEEK(d) date d Today is the day of the week, 1 Sunday, 2 Monday, and so on
SELECT DAYOFWEEK('2011-11-11 11:11:11'); ---- 返回6
16. UNIX_TIMESTAMP() gets the timestamp
SELECT UNIX_TIMESTAMP('2019-2-19'); SELECT UNIX_TIMESTAMP(expression); ---- 返回1550505600
17. FROM_UNIXTIME() timestamp to date
SELECT FROM_UNIXTIME(1550505600); ---- 返回2019-02-19 00:00:00 SELECT FROM_UNIXTIME(1550505600, '%Y-%m-%d'); ---- 返回2019-02-19
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