Define and use primary key : Primary Key « Key « SQL / MySQL





Define and use primary key

  
/*
mysql> Drop table Attributes;

mysql> CREATE TABLE Attributes
    -> (
    ->    ID SMALLINT NOT NULL PRIMARY KEY,
    ->    Settings TINYINT UNSIGNED NOT NULL
    -> );
Query OK, 0 rows affected (0.06 sec)

mysql> INSERT INTO Attributes VALUES (101, 58),
    ->                               (102, 73),
    ->                               (103, 45);
Query OK, 3 rows affected (0.00 sec)
Records: 3  Duplicates: 0  Warnings: 0

mysql> select * from Attributes;
+-----+----------+
| ID  | Settings |
+-----+----------+
| 101 |       58 |
| 102 |       73 |
| 103 |       45 |
+-----+----------+
3 rows in set (0.00 sec)

*/

Drop table Attributes;

CREATE TABLE Attributes
(
   ID SMALLINT NOT NULL PRIMARY KEY,
   Settings TINYINT UNSIGNED NOT NULL
);


INSERT INTO Attributes VALUES (101, 58), 
                              (102, 73), 
                              (103, 45);
select * from Attributes;

           
         
    
  










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