Adding primary key for not null column : Primary Key « Key « SQL / MySQL






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Adding primary key for not null column

     
mysql>
mysql> CREATE TABLE person
    -> (
    ->     tax_id INT UNSIGNED NOT NULL,
    ->     last_name CHAR(20),
    ->     first_name CHAR(20),
    ->     address CHAR(40),
    ->     PRIMARY KEY (tax_id)
    -> );
Query OK, 0 rows affected (0.00 sec)

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








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