I am trying to alter a table which has no primary key nor auto_increment column. I know how to add an auto increment primary key column.
I already have 500 rows in the DB and want to give them ids but I don't want to do it manually.
How do I insert data into the primary key column automatically?
An ALTER TABLE
statement adding the PRIMARY KEY
column works correctly in my testing:
ALTER TABLE tbl ADD id INT PRIMARY KEY AUTO_INCREMENT;
On a temporary table created for testing purposes, the above statement created the AUTO_INCREMENT
id
column and inserted auto-increment values for each existing row in the table, starting with 1.