Add primary key to existing table

Question

I have an existing table called Persion. In this table I have 5 columns:

• persionId
• Pname
• PMid
• Pdescription
• Pa

Answer 1

Try using this code:

ALTER TABLE `table name` 
    CHANGE COLUMN `column name` `column name` datatype NOT NULL, 
    ADD PRIMARY KEY (`column name`) ;