Jump to content


How to add a new column to table and make it pri key

  • Please log in to reply
1 reply to this topic

#1 OriginalSunny

  • Members
  • PipPipPip
  • Advanced Member
  • 95 posts

Posted 14 April 2006 - 10:44 PM

I am trying to add a new column to my table and making it the primary key. The problem is that i already have a primary key in the table. I cant seem to delete the column which is already the primary key and i cant seem to add the new column as i want to make it the primary key, and there is already a primary key in the table. So how do i do this??

Here is what i have tried and none of it works:

alter table emp add column ID int(5) auto_increment first; (empID is the new column i want to make the new primary key)

alter table emp drop index username; (username is the present primary i want to change)


#2 fenway

  • Staff Alumni
  • MySQL Si-Fu / PHP Resident Alien
  • 16,199 posts
  • LocationToronto, ON

Posted 16 April 2006 - 07:21 PM

Having already added the new column, you need to issue an ALTER TABLE statement with DROP PRIMARY KEY, ADD PRIMARY <yourNewCol> together, AFAIK.
Seriously... if people don't start reading this before posting, I'm going to consider not answering at all.

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users