SUBDATE

Sintassi

SUBDATE(data,INTERVAL espr unità), SUBDATE(espr, giorni)

Spiegazione

Quando si invoca con il secondo argomento nella forma INTERVAL, SUBDATE() è sinonimo di DATE_SUB(). Per informazioni sull'argomento INTERVAL unità, si veda DATE_ADD().

La seconda forma permette di passare l'argomento giorni come intero. In questo caso, viene considerato come il numero di giorni da sottrarre dell'espressione espr, che è di tipo DATE o DATETIME.

Esempi

MariaDB [(none)]> SELECT DATE_SUB('2008-01-02', INTERVAL 31 DAY);
+-----------------------------------------+
| DATE_SUB('2008-01-02', INTERVAL 31 DAY) |
+-----------------------------------------+
| 2007-12-02                              |
+-----------------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> SELECT SUBDATE('2008-01-02', INTERVAL 31 DAY);
+----------------------------------------+
| SUBDATE('2008-01-02', INTERVAL 31 DAY) |
+----------------------------------------+
| 2007-12-02                             |
+----------------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> 

MariaDB [(none)]> SELECT SUBDATE('2008-01-02 12:00:00', 31);
+------------------------------------+
| SUBDATE('2008-01-02 12:00:00', 31) |
+------------------------------------+
| 2007-12-02 12:00:00                |
+------------------------------------+
1 row in set (0.00 sec)

MariaDB [(none)]> 

CREATE TABLE t1 (d DATETIME);
INSERT INTO t1 VALUES
    ("2007-01-30 21:31:07"),
    ("1983-10-15 06:42:51"),
    ("2011-04-21 12:34:56"),
    ("2011-10-30 06:31:41"),
    ("2011-01-30 14:03:25"),
    ("2004-10-07 11:19:34");

MariaDB [test]> SELECT d, SUBDATE(d, 10) from t1;
+---------------------+---------------------+
| d                   | SUBDATE(d, 10)      |
+---------------------+---------------------+
| 2007-01-30 21:31:07 | 2007-01-20 21:31:07 |
| 1983-10-15 06:42:51 | 1983-10-05 06:42:51 |
| 2011-04-21 12:34:56 | 2011-04-11 12:34:56 |
| 2011-10-30 06:31:41 | 2011-10-20 06:31:41 |
| 2011-01-30 14:03:25 | 2011-01-20 14:03:25 |
| 2004-10-07 11:19:34 | 2004-09-27 11:19:34 |
+---------------------+---------------------+
6 rows in set (0.00 sec)

MariaDB [test]> SELECT d, SUBDATE(d, INTERVAL 10 MINUTE) from t1;
+---------------------+--------------------------------+
| d                   | SUBDATE(d, INTERVAL 10 MINUTE) |
+---------------------+--------------------------------+
| 2007-01-30 21:31:07 | 2007-01-30 21:21:07            |
| 1983-10-15 06:42:51 | 1983-10-15 06:32:51            |
| 2011-04-21 12:34:56 | 2011-04-21 12:24:56            |
| 2011-10-30 06:31:41 | 2011-10-30 06:21:41            |
| 2011-01-30 14:03:25 | 2011-01-30 13:53:25            |
| 2004-10-07 11:19:34 | 2004-10-07 11:09:34            |
+---------------------+--------------------------------+
6 rows in set (0.00 sec)