MySQL date function

MySQL Date function

• 1、DATE()
• 2、TIME()
• 3、TIMESTAMP()
• 4、NOW()、CURRENT_TIMESTAMP、CURRENT_TIMESTAMP()、SYSDATE()
• 5、STR_TO_DATE()
• 6、DATE_FORMAT()
• 7、UNIX_TIMESTAMP()
• 8、FROM_UNIXTIME
• 9、 Other date functions
• 10、 Date format

1、DATE()

return date . Format ：YYYY-MM-DD

SELECT DATE(NOW());
> 2022-04-04

2、TIME()

return date . Format ：HH-mm-ss

SELECT TIME(NOW());
> 16:25:09

3、TIMESTAMP()

return Date time . Format ：YYYY-MM-DD HH-mm-ss

SELECT TIMESTAMP(NOW());
> 2022-04-04 16:31:12

4、NOW()、CURRENT_TIMESTAMP、CURRENT_TIMESTAMP()、SYSDATE()

select NOW(),CURRENT_TIMESTAMP,CURRENT_TIMESTAMP();
> 2022-04-04 16:40:03	2022-04-04 16:40:03	2022-04-04 16:40:03

It should be noted that the first three are ** Returns the time when the statement execution started **, the latter **SYSDATE() Different Returns the time when this function was executed **

select SLEEP(1),NOW(),CURRENT_TIMESTAMP,CURRENT_TIMESTAMP(),SYSDATE();
> 0 2022-04-04 16:42:22	2022-04-04 16:42:22	2022-04-04 16:42:22	2022-04-04 16:42:23

Here we can see that we use sleep(1), Give Way sql Delay a second to get the first three and seelp(1) The difference between SYSDATE() Obvious ratio NOW() These are more than a second , So we can know The expected result is before and after the delay now() The time corresponding to the function does not change ,sysdate() The time of is equal to the previous time plus the delay time

5、STR_TO_DATE()

According to the specified format , Pass the string to the corresponding date or date type

 example 1、
SELECT STR_TO_DATE('2022-04-04 22:50:17','%Y-%m-%d');
> 2022-04-04
 When there are no hours, minutes and seconds, the display is ignored here 

 example 2、
SELECT STR_TO_DATE('2022-04-04 22:50:17','%Y-%m-%d %H');
> 2022-04-04 22:00:00

6、DATE_FORMAT()

Return the date as the corresponding string according to the specified format
More date formats

 example 1、
SELECT DATE_FORMAT('2022-04-04 22:50:17','%Y-%m-%d');
> 2022-04-04

 example 2、
SELECT DATE_FORMAT('2022-04-04 22:50:17','%Y-%m-%d %H');
> 2022-04-04 22

7、UNIX_TIMESTAMP()

Get the timestamp of the date （10 position ）

SELECT unix_timestamp(now());
> 1649083817

8、FROM_UNIXTIME

According to time stamp （10 position ） Return date

 example 1、
SELECT FROM_UNIXTIME(1649087115)
> 2022-04-04 23:45:15

 example 2、 Add the second parameter   format 
SELECT FROM_UNIXTIME(1649087115,'%Y-%m-%s')
> 2022-04-15

9、 Other date functions

Function name

describe

Examples

result

NOW()

Get current date Format ’yyyy-MM-dd HH:mm:ss’

select NOW();

2022-04-04 22:50:17

CURDATE()

Get current date Format ’yyyy-MM-dd’

select CURDATE();

2022-04-04

CURTIME()

Get current date Format ’HH:mm:ss’

select CURTIME();

22:50:17

CURRENT_TIMESTAMP()

Get current date Format ’yyyy-MM-dd HH:mm:ss’

select CURRENT_TIMESTAMP();

2022-04-04 22:50:17

CURRENT_DATE()

Get current date Format ’yyyy-MM-dd’

select CURRENT_DATE();

2022-04-04

CURRENT_TIME()

Get current date Format ’HH:mm:ss’

select CURRENT_TIME();

22:50:17

CURRENT_TIMESTAMP

Get current date Format ’yyyy-MM-dd HH:mm:ss’

select CURRENT_TIMESTAMP;

2022-04-04 22:50:17

CURRENT_DATE

Get current date Format ’yyyy-MM-dd’

select CURRENT_DATE;

2022-04-04

CURRENT_TIME

Get current date Format ’HH:mm:ss’

select CURRENT_TIME;

22:50:17

SYSDATE()

Get the execution time of this function Format ’yyyy-MM-dd HH:mm:ss’

select SYSDATE;

2022-04-04 22:50:17

YEAR()

Get year

select YEAR(NOW()) ;

2022

MONTH()

Get month

select MONTH(NOW())

4

DAYOFMONTH()

Get the number of days in the month

select DAYOFMONTH(NOW())

4

DAYOFYEAR()

Get the number of days in the year

select DAYOFYEAR(NOW())

94

WEEKDAY()

The acquisition date is the day of the week (0- On behalf of Monday 、1- On behalf of Tuesday )

select WEEKDAY(NOW());

0

DAYOFWEEK()

The acquisition date is the day of the week (1- For Sunday 、2- On behalf of Monday )

select DAYOFWEEK(NOW());

2

WEEKOFYEAR()

The acquisition date is the week of the year

select WEEKOFYEAR(NOW());

14

TO_DAYS()

Get from 0000-00-00 Days to date

SELECT TO_DAYS(NOW());

738614

HOUR()

For hours

SELECT HOUR(NOW());

22

MINUTE()

Get minutes

SELECT MINUTE(NOW());

50

SECOND()

Get seconds

SELECT SECOND(NOW());

17

10、 Date format

Format

describe

%Y

year ,4 position

%y

year ,2 position

%M

month English representation January

%b

month English abbreviation means Apr

%m

month , The number (00-12)

%c

month , The number (0-12)

%d

Day of the month , The number (00-31)

%e

Day of the month , The number (0-31)

%j

Days of (001-366)

%H

Hours (00-23)

%I

Hours (01-12) 0 Time representative 12 1 Time representative 1

%k

Hours (0-23)

%i

minute , The number (00-59)

%S

second (00-59)

%s

second (00-59)

%f

Microsecond

%T

Time , 24- Hours (hh:mm:ss)

%r

Time ,12- Hours （hh:mm:ss AM or PM）

%p

AM or PM

%a

The abbreviation of the name of the week for example Mon

%W

Week name for example Monday

%w

Days of the week （0= Sunday , 6= Saturday ）

%U

Zhou (00-53) Sunday is the first day of the week

%u

Zhou (00-53) Monday is the first day of the week

%V

Zhou (01-53) Sunday is the first day of the week , And %X Use

%v

Zhou (01-53) Monday is the first day of the week , And %x Use

%X

year , Sunday is the first day of the week ,4 position , And %V Use

%x

year , Monday is the first day of the week ,4 position , And %v Use