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Posted by abhradeep mazumdar
abhradeep mazumdar
551 Points

MySQL query for adding primary key

In the Question : Alter the "t_movies" table to add an auto incrementing primary key called "pk_id" first.

My response is : alter table t_movies add pk_id first add primary key auto_increment;

other alter statement which I could think of are : alter table t_movies add primary key pk_id auto_increment;

None seem to work. Please help

3 Answers

nnuxiragwh
nnuxiragwh
10,345 Points
nnuxiragwh
nnuxiragwh
10,345 Points

I think that the only thing missing here is the INT data type for your pk_id.

Try: ALTER TABLE t_movies ADD pk_id INT PRIMARY KEY AUTO_INCREMENT FIRST;

I did not tested it, so I'm not sure if it is working.

abhradeep mazumdar
abhradeep mazumdar
551 Points
abhradeep mazumdar
abhradeep mazumdar
551 Points

Thank you Tomasz : Your solution worked, as it is I am facing problems in framing SQL.

Is it mandatory that "FIRST" has to be put at the end of the statement.

I mean will this statement be wrong :

alter table t_movies add pk_id int primary key first auto_increment;

Santiago Barrionuevo
Santiago Barrionuevo
14,176 Points
Santiago Barrionuevo
Santiago Barrionuevo
14,176 Points

This works:

ALTER TABLE t_movies ADD COLUMN pk_id INT PRIMARY KEY AUTO_INCREMENT FIRST;

Thanks Tomasz!