How does MySQL use addition and subtraction operators for date operations?

MySQL can perform date arithmetic using the addition and subtraction operators by adding the INTERVAL keyword to a time unit, date, or datetime.

Example 1

Add 2 days to a specific date.

mysql> Select '2017-05-20' + INTERVAL 2 day; +-------------------------------+ | '2017-05-20' + INTERVAL 2 day | +-------------------------------+ | 2017-05-22 | +-------------------------------+ 1 row in set (0.00 sec)

Example 2

Subtract 2 days from a specific date.

mysql> Select '2017-05-20' - INTERVAL 2 day; +-------------------------------+ | '2017-05-20' - INTERVAL 2 day | +-------------------------------+ | 2017-05-18 | +-------------------------------+ 1 row in set (0.00 sec)

Example 3

Add 2 hours of time.

mysql> Select '2017-05-20 05:04:35' + INTERVAL 3 hour; +-----------------------------------------+ | '2017-05-20 05:04:35' + INTERVAL 3 hour | +-----------------------------------------+ | 2017-05-20 08:04:35 | +-----------------------------------------+ 1 row in set (0.00 sec)

Example 4

Add one month to a specific date

mysql> Select '2017-05-20 05:04:35' + INTERVAL 1 month; +------------------------------------------+ | '2017-05-20 05:04:35' + INTERVAL 1 month | +------------------------------------------+ | 2017-06-20 05:04:35 | +------------------------------------------+ 1 row in set (0.00 sec)

In this way, with the INTERVAL keyword, we can perform date operations.

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