Finding duplicate values in a SQL table - ADVANCED

Posted by Alex on Stack Overflow See other posts from Stack Overflow or by Alex
Published on 2010-04-07T18:17:29Z Indexed on 2010/04/07 18:23 UTC
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duplicates

It's easy to find duplicates with one field

SELECT name, 
 COUNT(email) 
FROM users
GROUP BY email
HAVING ( COUNT(email) > 1 )

So if we have a table

ID   NAME   EMAIL
1    John   [email protected]
2    Sam    [email protected]
3    Tom    [email protected]
4    Bob    [email protected]
5    Tom    [email protected]

This query will give us John, Sam, Tom, Tom because they all have the same e-mails.

But what I want, is to get duplicates with the same e-mails and names.

I want to get Tom, Tom.

I made a mistake, and allowed to insert duplicate name and e-mail values. Now I need to remove/change the duplicates. But I need to find them first.

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Finding duplicate values in a SQL table - ADVANCED - Developer IT

Finding duplicate values in a SQL table - ADVANCED

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duplicates

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