From: Date: December 22 2005 3:19am
Subject: RE: Are primary keys essential?
List-Archive: http://lists.mysql.com/mysql/193152
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Hi James,

Not AFAIK, one can create tables without specifying a PK and there is no
objection. Data is stored quite happily and you should be able to use
your FK's to access other data. It must be voluntary because the ALTER
TABLE DML statement has

DROP PRIMARY KEY drops the primary index. Note: In older versions of
MySQL, if no primary index existed, then DROP PRIMARY KEY would drop the
first UNIQUE  index in the table. This is not the case in MySQL 5.0,
where trying to use DROP PRIMARY KEY on a table with no primary key will
give rise to an error.=20

Regards

David Logan=20
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Adelaide 5000=20
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-----Original Message-----
From: James Harvard [mailto:james.lists.tech@stripped]=20
Sent: Thursday, 22 December 2005 12:45 PM
To: mysql@stripped
Subject: Re: Are primary keys essential?

In hindsight my thread title was misleading - sorry. Should have been
"are primary keys _always_ essential?".
JH

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