# Date And Time Arithmetic
__*DATE_ADD function*__
__*DATE_SUB function*__
__*INTERVAL function*__
+ **`DATE_ADD, DATE_SUB`** 
+ **`+/- INTERVAL`** 
```12
tidb> SELECT NOW() + INTERVAL '1 12:12:12.123456' ~!@DAY_MICROSECOND@!~,
    -> NOW() + INTERVAL '12.123456' ~!@SECOND_MICROSECOND@!~,
    -> NOW() - INTERVAL '1-3' ~!@YEAR_MONTH@!~,
    -> DATE_ADD(NOW(), INTERVAL 1 ~!@WEEK@!~),
    -> DATE_SUB(NOW(), INTERVAL 1 ~!@QUARTER@!~)
    -> \G
*************************** 1. row***************************
NOW() + INTERVAL '1 12:12:12.123456' DAY_MICROSECOND: 2022-01-07 22:29:02.123456
     NOW() + INTERVAL '12.123456' SECOND_MICROSECOND: 2022-01-06 10:17:02.123456
                   NOW() - INTERVAL '1-3' YEAR_MONTH: 2020-10-06 10:16:50
                    DATE_ADD(NOW(), INTERVAL 1 WEEK): 2022-01-13 10:16:50
                 DATE_SUB(NOW(), INTERVAL 1 QUARTER): 2021-10-06 10:16:50
```

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DATE_ADD () adds a time INTERVAL to a date
DATE_SUB () subtracts a specified time INTERVAL from a date