Learning Mysql

+---------+------+-------------------------------------------------+
1 row inset sec)
Displaying the contents of the table, you can see that when you try to store anything that’s not in the valid values, an empty string is stored instead:
mysql> SELECT * FROM fruits_enum;
+------------+
| fruit_name |
+------------+
| Apple |
| |
| |
+------------+
3 rows inset sec)
You can also specify a default value other than the empty string:
mysql> CREATE TABLE new_fruits_enum ( fruit_name ENUM('Apple', 'Orange, 'Pear')
-> DEFAULT 'Pear');
Query OK, 0 rows affected (0.01 sec)
mysql> INSERT INTO new_fruits_enum VALUES();
Query OK, 1 row affected (0.00 sec)
mysql> SELECT * FROM new_fruits_enum;
+------------+
| fruit_name |
+------------+
| Pear |
+------------+
1 row inset sec)
Here, not specifying a value results in the default value Pear being stored.
SET('value1'[,'value2'[, A set of string values. A column of type
SET
can beset to zero or more values from the list
value1
,
value2
, and soon, up to a maximum of 64 different values. While the values are strings, what’s stored in the database is an integer representation.
SET
differs from
ENUM
in that each row can store only one
ENUM
value in a column,
but can store multiple
SET
values. This type is useful for storing a selection of choices from a list, such as user preferences. Consider this example using fruit names the name can be any combination of the predefined values:
mysql> CREATE TABLE fruits_set ( fruit_name SET('Apple', 'Orange, 'Pear) );
Query OK, 0 rows affected (0.01 sec)
mysql> INSERT INTO fruits_set VALUES ('Apple');
Query OK, 1 row affected (0.00 sec)
mysql> INSERT INTO fruits_set VALUES ('Banana');
Query OK, 1 row affected, 1 warning (0.00 sec)
mysql> SHOW WARNINGS;
+---------+------+-------------------------------------------------+

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