Create table: unique value and value from combined columns : Unique « Select Clause « SQL / MySQL

1. SQL / MySQL
2. Select Clause
3. Unique

Create table: unique value and value from combined columns

/*
mysql> Drop table Product;

mysql> CREATE TABLE Product
    -> (
    ->    ID SMALLINT UNSIGNED NOT NULL,
    ->    ModelID SMALLINT UNSIGNED NOT NULL,
    ->    ModelDescrip VARCHAR(40),
    ->    PRIMARY KEY (ID),
    ->    UNIQUE (ID, ModelID)
    -> );
Query OK, 0 rows affected (0.06 sec)

mysql> Describe Product;
+--------------+----------------------+------+-----+---------+-------+
| Field        | Type                 | Null | Key | Default | Extra |
+--------------+----------------------+------+-----+---------+-------+
| ID           | smallint(5) unsigned |      | PRI | 0       |       |
| ModelID      | smallint(5) unsigned |      |     | 0       |       |
| ModelDescrip | varchar(40)          | YES  |     | NULL    |       |
+--------------+----------------------+------+-----+---------+-------+
3 rows in set (0.00 sec)


*/

Drop table Product;

  
CREATE TABLE Product
(
   ID SMALLINT UNSIGNED NOT NULL,
   ModelID SMALLINT UNSIGNED NOT NULL,
   ModelDescrip VARCHAR(40),
   PRIMARY KEY (ID),
   UNIQUE (ID, ModelID)
);

Describe Product;

           
       

Related examples in the same category