From: Robert D. Lang CEO Date: March 23 1999 10:03pm Subject: Problem Solved Re: Duplicate Keys. List-Archive: http://lists.mysql.com/mysql/881 Message-Id: <36F80FBF.65B7801B@rdlcom.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Exactly Thimble! One primary key over two fields. But no problem. As I already wrote to Christian, the problem stemmed from a perl script we are using to input data into the database ; not stating the host field with the primary key attribute. I changed this and it now works fine. Thanks to all. Sometimes I don't know who to contact, perl programmers or mysql programmers on problems. This error message kept stating a sql can't write error. It was the script not being able to input data. The mysql program was working fine. Thimble Smith wrote: > Christian, I think he's not talking about the mysql.user table. > I think he's got a his_db.user table that has 'host' and 'user' > fields in it. > > Robert, it would be very helpful in the future if you can be more > exact when specifying problems.  It's not possible to have two > primary keys in one table - you can have only one primary key. > I assume you mean a primary key over two fields, e.g.: > >     PRIMARY KEY (host, user) > > If you need to remove a row, just use DELETE: > >     DELETE FROM user WHERE host='some host' AND user='some user' > > BUT, if you need to do this regularly then it's quite clear that > your database design is very far from correct, or else your > program is doing a lot of work that is not necessary. > > If neither Christian's answer nor mine is sufficient to get you > past your current dilemma, please do write the list again with > a better description of what's going on.  I realize that some of > the terminology can be hard to get a grasp on - when in doubt, > cut and paste commands (and their output) that show exactly what > you're struggling with.  That avoids terminology altogether, it > can be readily duplicated by anyone, etc. > > Tim > > On Tue, Mar 23, 1999 at 09:13:34PM +0100, Christian Mack wrote: > >"Robert D. Lang CEO" wrote: > >>Dear Mysql Users:  I have two primary keys in a mysql table > >>called, " user." They are for host and user fields. I am having > >>a conflict with regards to updating due to this. I need to > >>remove one of the primary keys so I do not have a conflict when > >>writing to the database mysql. > >> > >>The error message is: mysql::st execute failed: Can't write, > >>duplicate key in table 'user. > >> > >>I am new to mysql, so I am asking what is the command line needed to remove a > >>primary key from a field? > > > >Sorry, but this seems nonsens to me. > >Why do you want to use one 'user name' with the same 'from host' > >several times? -- Sincerely, Robert D. Lang CEO RDL Communications Inc. Speak To Us: rdlcom@stripped   See Us: www.rdlcom.com