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/*
mysql> Drop TABLE Employee;
Query OK, 0 rows affected (0.00 sec)
mysql> CREATE TABLE Employee (
-> Name VARCHAR(50) PRIMARY KEY NOT NULL,
-> Phone VARCHAR(15) DEFAULT 'Unknown Phone',
-> Age INT,
-> CONSTRAINT CheckAge CHECK (Age BETWEEN 20 and 30));
Query OK, 0 rows affected (0.05 sec)
mysql> Describe Employee;
+-------+-------------+------+-----+---------------+-------+
| Field | Type | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------------+-------+
| Name | varchar(50) | | PRI | | |
| Phone | varchar(15) | YES | | Unknown Phone | |
| Age | int(11) | YES | | NULL | |
+-------+-------------+------+-----+---------------+-------+
3 rows in set (0.00 sec)
mysql> INSERT INTO Employee (Name, Phone, Age) VALUES ('Joe Yin', '666 2323', 26
);
Query OK, 1 row affected (0.00 sec)
mysql> INSERT INTO Employee (Name, Age) VALUES ('John Doe', 31);
Query OK, 1 row affected (0.01 sec)
mysql> INSERT INTO Employee (Name, Phone) VALUES ('Joe Yin', NULL);
ERROR 1062 (23000): Duplicate entry 'Joe Yin' for key 1
mysql> Select * from Employee;
+----------+---------------+------+
| Name | Phone | Age |
+----------+---------------+------+
| Joe Yin | 666 2323 | 26 |
| John Doe | Unknown Phone | 31 |
+----------+---------------+------+
2 rows in set (0.00 sec)
*/
Drop TABLE Employee;
CREATE TABLE Employee (
Name VARCHAR(50) PRIMARY KEY NOT NULL,
Phone VARCHAR(15) DEFAULT 'Unknown Phone',
Age INT,
CONSTRAINT CheckAge CHECK (Age BETWEEN 20 and 30));
Describe Employee;
INSERT INTO Employee (Name, Phone, Age) VALUES ('Joe Yin', '666 2323', 26);
INSERT INTO Employee (Name, Age) VALUES ('John Doe', 31);
INSERT INTO Employee (Name, Phone) VALUES ('Joe Yin', NULL);
Select * from Employee;
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