DATE_ADD

Sintassi

DATE_ADD(data, INTERVAL espr unità), DATE_SUB(data, INTERVAL espr unità)

Spiegazione

Queste funzioni effettuando un calcolo aritmetico sulle date. L'argomento data specifica il valore iniziale di tipo date o datetime. espr è un'espressione che specifica l'intervallo da aggiungere o sottrarre alla data iniziale. espr è una stringa; può iniziare con "-" per gli intervalli negativi. unità rappresenta una parola riservata che indica l'unità di misura delle relative espressioni.

Esempi

MariaDB [(none)]> SELECT '2008-12-31 23:59:59' + INTERVAL 1 SECOND;
+-------------------------------------------+
| '2008-12-31 23:59:59' + INTERVAL 1 SECOND |
+-------------------------------------------+
| 2009-01-01 00:00:00                       |
+-------------------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> SELECT INTERVAL 1 DAY + '2008-12-31';
+-------------------------------+
| INTERVAL 1 DAY + '2008-12-31' |
+-------------------------------+
| 2009-01-01                    |
+-------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> SELECT '2005-01-01' - INTERVAL 1 SECOND;
+----------------------------------+
| '2005-01-01' - INTERVAL 1 SECOND |
+----------------------------------+
| 2004-12-31 23:59:59              |
+----------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> SELECT DATE_ADD('2000-12-31 23:59:59',
    -> INTERVAL 1 SECOND);
+----------------------------------------------------+
| DATE_ADD('2000-12-31 23:59:59', INTERVAL 1 SECOND) |
+----------------------------------------------------+
| 2001-01-01 00:00:00                                |
+----------------------------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> SELECT DATE_ADD('2010-12-31 23:59:59',
    -> INTERVAL 1 DAY);
+-------------------------------------------------+
| DATE_ADD('2010-12-31 23:59:59', INTERVAL 1 DAY) |
+-------------------------------------------------+
| 2011-01-01 23:59:59                             |
+-------------------------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> SELECT DATE_ADD('2100-12-31 23:59:59',
    -> INTERVAL '1:1' MINUTE_SECOND);
+---------------------------------------------------------------+
| DATE_ADD('2100-12-31 23:59:59', INTERVAL '1:1' MINUTE_SECOND) |
+---------------------------------------------------------------+
| 2101-01-01 00:01:00                                           |
+---------------------------------------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> SELECT DATE_SUB('2005-01-01 00:00:00',
    -> INTERVAL '1 1:1:1' DAY_SECOND);
+----------------------------------------------------------------+
| DATE_SUB('2005-01-01 00:00:00', INTERVAL '1 1:1:1' DAY_SECOND) |
+----------------------------------------------------------------+
| 2004-12-30 22:58:59                                            |
+----------------------------------------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> SELECT DATE_ADD('1900-01-01 00:00:00',
    -> INTERVAL '-1 10' DAY_HOUR);
+------------------------------------------------------------+
| DATE_ADD('1900-01-01 00:00:00', INTERVAL '-1 10' DAY_HOUR) |
+------------------------------------------------------------+
| 1899-12-30 14:00:00                                        |
+------------------------------------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> SELECT DATE_SUB('1998-01-02', INTERVAL 31 DAY);
+-----------------------------------------+
| DATE_SUB('1998-01-02', INTERVAL 31 DAY) |
+-----------------------------------------+
| 1997-12-02                              |
+-----------------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> SELECT DATE_ADD('1992-12-31 23:59:59.000002',
    -> INTERVAL '1.999999' SECOND_MICROSECOND);
+--------------------------------------------------------------------------------+
| DATE_ADD('1992-12-31 23:59:59.000002', INTERVAL '1.999999' SECOND_MICROSECOND) |
+--------------------------------------------------------------------------------+
| 1993-01-01 00:00:01.000001                                                     |
+--------------------------------------------------------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]>