Nebo možná živá i mrtvá zároveň…
-
mysql> CREATE TABLE cats (
-
mysql> owner_name VARCHAR(50),
-
mysql> is_alive ENUM('alive', 'dead') NOT NULL);
-
Query OK, 0 rows affected (0.07 sec)
-
-
mysql> INSERT INTO cats VALUES ('Erwin Schrödinger', '');
-
Query OK, 1 row affected, 1 warning (0.00 sec)
-
-
mysql> SELECT * FROM cats WHERE is_alive = 'alive';
-
Empty SET (0.00 sec)
-
-
mysql> SELECT * FROM cats WHERE is_alive = 'dead';
-
Empty SET (0.00 sec)
-
-
mysql> SELECT * FROM cats WHERE is_alive = '';
-
+===================+==========+
-
| owner_name | is_alive |
-
+===================+==========+
-
| Erwin Schrödinger | |
-
+===================+==========+
-
1 row IN SET (0.00 sec)