Today I Learned

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Doing Date Math In MySQL

MySQL has an array of functions for interacting with date and datetime values. If you’d like to do math with a date to compute a date in the future or the past, you can use the DATE_ADD() and DATE_SUB() functions.

mysql> select now() Now, date_add(now(), interval 10 minute) '10 Minutes Later';
+---------------------+---------------------+
| Now                 | 10 Minutes Later    |
+---------------------+---------------------+
| 2018-10-18 15:53:29 | 2018-10-18 16:03:29 |
+---------------------+---------------------+

mysql> select now() Now, date_sub(now(), interval 9 day) '9 Days Earlier';
+---------------------+---------------------+
| Now                 | 9 Days Earlier      |
+---------------------+---------------------+
| 2018-10-18 15:54:01 | 2018-10-09 15:54:01 |
+---------------------+---------------------+

There are equivalent ADDDATE() and SUBDATE() functions if you prefer.

Check out the docs for more details.

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