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ENUM

Sintassi

ENUM('valore1','valore2',...) [CHARACTER SET set_di_caratteri] [COLLATE nome_collation]

Spiegazione

Una enumerazione. Un oggetto stringa che può avere un solo valore, scelto dalla lista di valori 'valore1', 'valore2', ..., NULL o il valore di errore ''. Una colonna ENUM può avere un massimo di 65,535 valori distinti. I valori ENUM internamente sono rappresentati come interi.

Esempi

MariaDB [test]> create table frutta (
    -> id INT NOT NULL auto_increment PRIMARY KEY,
    -> fruit ENUM('mela','arancia','pera'),
    -> bushels INT);
Query OK, 0 rows affected (0.30 sec)

MariaDB [test]> describe frutta;
+---------+-------------------------------+------+-----+---------+----------------+
| Field   | Type                          | Null | Key | Default | Extra          |
+---------+-------------------------------+------+-----+---------+----------------+
| id      | int(11)                       | NO   | PRI | NULL    | auto_increment |
| frutto  | enum('mela','arancia','pera') | YES  |     | NULL    |                |
| cesti   | int(11)                       | YES  |     | NULL    |                |
+---------+-------------------------------+------+-----+---------+----------------+
3 rows in set (0.03 sec)

MariaDB [test]> INSERT INTO frutta
    -> (frutto,cesti) VALUES
    -> ('pera',20),
    -> ('mela',100),
    -> ('arancia',25);
Query OK, 3 rows affected (0.14 sec)
Records: 3  Duplicates: 0  Warnings: 0

MariaDB [test]> INSERT INTO frutta
    -> (frutto,cesti) VALUES
    -> ('avocado',10);
ERROR 1265 (01000): Data truncated for column 'fruit' at row 1

MariaDB [test]> select * from fruits;
+----+---------+---------+
| id | frutto  | cesti   |
+----+---------+---------+
|  1 | pera    |      20 |
|  2 | mela    |     100 |
|  3 | arancia |      25 |
+----+---------+---------+
3 rows in set (0.01 sec)

MariaDB [test]> 

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