Maybe you should view this article: http://blog.chinaunix.net/u/29134/showart_375303.html
On Feb 12, 2008 8:32 AM, Grant Limberg <[EMAIL PROTECTED]> wrote: > Something like this should help you find all of the dupes > > select email_address from table > group by email_address > having count(*)>1; > > On Feb 11, 2008 4:23 PM, Ferindo Middleton <[EMAIL PROTECTED]> > wrote: > > > I have a table (customers) without a primary key. I want to make the > > email_address field the primary key, only problem is, several records > > already share the same email_address > > > > How do I write a query which will show me all the instances where > > email_address is duplicated throughout the table. > > > > -- > > Ferindo > > > > > > -- > Grant Limberg > [EMAIL PROTECTED] > -- I'm a mysql DBA in china. More about me just visit here: http://yueliangdao0608.cublog.cn
