Commands for Mysql date calculation
This article mainly introduces "the command of Mysql date calculation". In the daily operation, I believe that many people have doubts about the command of Mysql date calculation. The editor consulted all kinds of data and sorted out simple and easy-to-use operation methods. I hope it will be helpful to answer the doubts of "Mysql date calculation command". Next, please follow the editor to study!
MySQL adds a time interval to the date with the date_add () function
MySQL subtracts a time interval from the date using the date_sub () function
The experiments are as follows:
Mysql > select now ()
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| | now () |
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| | 2017-03-15 16:57:30 |
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1 row in set (0.00 sec)
Mysql > set @ dt = now ()
Query OK, 0 rows affected (0.00 sec)
Add one day:
Mysql > select date_add (@ dt, interval 1 day)
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| | date_add (@ dt, interval 1 day) | |
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| | 2017-03-16 16:57:32 |
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1 row in set (0.00 sec)
One day less:
Mysql > select date_sub (@ dt, interval 1 day)
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| | date_sub (@ dt, interval 1 day) | |
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| | 2017-03-14 16:57:32 |
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1 row in set (0.00 sec)
By the same token, an additional hour and a minute can be used:
Select date_add (@ dt, interval 1 hour);-- add one hour
Select date_add (@ dt, interval 1 minute);-- add one minute
Select date_add (@ dt, interval 1 second);-- add one second
Select date_add (@ dt, interval 1 microsecond);-- add a nuance
Select date_add (@ dt, interval 1 week);-- add one week
Select date_add (@ dt, interval 1 month);-- add one month
Select date_add (@ dt, interval 1 quarter); add one quarter (three months)
One hour less, one minute can be used:
Select date_sub (@ dt, interval 1 hour);-- one hour less
Select date_sub (@ dt, interval 1 minute);-- one minute less
Select date_sub (@ dt, interval 1 second);-- one second less
Select date_sub (@ dt, interval 1 microsecond);-- reduce a little bit
Select date_sub (@ dt, interval 1 week);-- one week less
Select date_sub (@ dt, interval 1 month);-- one month less
Select date_sub (@ dt, interval 1 quarter);-reduced by one quarter (three months)
At this point, the study of "Mysql date calculation command" is over. I hope to be able to solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!
