Remove Primary Key constraint from a table column in MySQL

Subash Chandran 23rd September 2020 Leave a Comment

Find out how to remove a Primary Key constraint from a table column in MySQL

Syntax

alter table table_name DROP PRIMARY KEY;

Example

mysql> DESCRIBE employee;

+-------+-------------+------+-----+---------+-------+
| Field | Type        | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id    |  int(11)    | NO   | PRI | NULL    |       |
| name  | varchar(20) | YES  |     | NULL    |       |
+-------+-------------+------+-----+---------+-------+


mysql> alter table employee DROP PRIMARY KEY;
Query OK, 0 rows affected (0.31 sec)
Records: 0  Duplicates: 0  Warnings: 0


mysql> DESCRIBE employee;

+-------+-------------+------+-----+---------+-------+
| Field | Type        | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id    |  int(11)    | NO   |     | NULL    |       |
| name  | varchar(20) | YES  |     | NULL    |       |
+-------+-------------+------+-----+---------+-------+

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Solutions

Can we remove a primary key from MySQL table?, How can I define a column of a MySQL table PRIMARY KEY without using the PRIMARY KEY keyword?, How can I drop an existing column from a MySQL table?, How can we add a FOREIGN KEY constraint to the field of an existing MySQL table?, How can we apply a NOT NULL constraint to a column of an existing MySQL table?, How can we apply the PRIMARY KEY constraint to the field of an existing MySQL table?, How can we apply UNIQUE constraint to the field of an existing MySQL table?, How can we drop UNIQUE constraint from a MySQL table?, How can we remove a column from MySQL table?, How can we remove composite PRIMARY KEY constraint applied on multiple columns of an existing MySQL table?, How can we remove FOREIGN KEY constraint from a column of an existing MySQL table?, How can we remove NOT NULL constraint from a column of an existing MySQL table?, How can we set PRIMARY KEY on multiple columns of a MySQL table?, How can we set PRIMARY KEY on multiple columns of an existing MySQL table?, Set existing column as Primary Key in MySQL?

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