Answers for "mysql make primary key"

mysql change 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 get primary keys of table

SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA = 'Your Database'
  AND TABLE_NAME = 'Your Table name'
  AND COLUMN_KEY = 'PRI';


SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA = 'Your Database'
  AND TABLE_NAME = 'Your Table name'
  AND COLUMN_KEY = 'UNI';