Mysql set primary key

ALTER TABLE tableName MODIFY COLUMN id INT; /* First you should drop auto increment */
ALTER TABLE tableName DROP PRIMARY KEY; /* Dop primary key */
ALTER TABLE tableName ADD PRIMARY KEY (new_id); /* Set primary key to the new column */
ALTER TABLE tableName MODIFY COLUMN new_id INT AUTO_INCREMENT; /* Set auto increment to the new primary key */

Mysql drop key

ALTER TABLE tbl_quiz_attempt_master
  DROP INDEX `PRIMARY`;

Source: stackoverflow.com

Similar codes

-1 vote294 views1 answer
Mysql select all columns and specific fields as
SQL
103 votes492 views2 answers
Sql server LIKE '%%'
SQL
0 vote301 views1 answer
Sql developer connect to sql server
SQL
0 vote309 views1 answer
Supprimer les valeur d'une table mysql
SQL
0 vote294 views1 answer
Mysql grant access to one database
SQL
0 vote284 views1 answer
Sql track modification
SQL
0 vote292 views1 answer
Mysql find missing values
SQL
1 vote297 views1 answer
Select count distinct multiple columns sql server
SQL
0 vote279 views1 answer
Sqlalchemy.exc.DBAPIError: (ibm_db_dbi.Error) ibm_db_dbi::Error: SystemError('<built-in function connect> returned NULL without setting an error')
SQL
12 votes296 views6 answers
Select distinct
SQL