Create table: two columns for primary key : Create Table « Table Index « SQL / MySQL





Create table: two columns for primary key

   
/*
mysql> Drop table Orders;

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

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

*/
Drop table Orders;

  
CREATE TABLE Orders
(
   ID SMALLINT UNSIGNED NOT NULL,
   ModelID SMALLINT UNSIGNED NOT NULL,
   Descrip VARCHAR(40),
   PRIMARY KEY (ID, ModelID)
);

Describe Orders;

           
         
    
    
  










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