Scott Haneda <[EMAIL PROTECTED]> wrote on 10/20/2005 08:11:27 PM: > I dropped a field in a table, I have a backup, so is what I have done is > imported the backup of the table to a new table, so I have table "sessions" > which has a empty field for "session_key" > > I now have sessions_backup which has all the data, there is a pk called id > > I need to run a sql update that will pull the session_key from the backup > table, and update the sesssions table with it, based in the field id=id. > > Can someone help me, I am pretty sure I know what to do, but don't want to > risk messing it up. > > thanks > -- > ------------------------------------------------------------- > Scott Haneda Tel: 415.898.2602 > <http://www.newgeo.com> Novato, CA U.S.A. > >
Assuming that your MySQL version supports multiple table updates: UPDATE sessions s INNER JOIN sessionbackup sb ON sb.id = s.id SET s.session_key = sb.session_key; even if this screws up (which it really shouldn't), you can re-blank your session_key and try again with: UPDATE session SET session_key = NULL; Shawn Green Database Administrator Unimin Corporation - Spruce Pine