Drop primary key : Primary Key « Key « SQL / MySQL






  1. SQL / MySQL
  2. Key
  3. Primary Key

Drop primary key

     
mysql>
mysql>
mysql> CREATE TABLE EmployeeS(
    ->          EmployeeNO       INTEGER      NOT NULL,
    ->          NAME           CHAR(15)     NOT NULL,
    ->          INITIALS       CHAR(3)      NOT NULL,
    ->          BIRTH_DATE     DATE                 ,
    ->          SEX            CHAR(1)      NOT NULL,
    ->          JOINED         SMALLINT     NOT NULL,
    ->          STREET         VARCHAR(30)  NOT NULL,
    ->          HOUSENO        CHAR(4)              ,
    ->          POSTCODE       CHAR(6)              ,
    ->          TOWN           VARCHAR(30)  NOT NULL,
    ->          PHONENO        CHAR(13)             ,
    ->          LEAGUENO       CHAR(4)              ,
    ->          PRIMARY KEY    (EmployeeNO)           );
Query OK, 0 rows affected (0.00 sec)

mysql>
mysql> ALTER TABLE EmployeeS DROP PRIMARY KEY;
Query OK, 0 rows affected (0.01 sec)
Records: 0  Duplicates: 0  Warnings: 0

mysql>
mysql> drop table Employees;
Query OK, 0 rows affected (0.00 sec)

mysql>








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