SQL:Finding Duplicates with SQL

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Do you want to find duplicates in a table.
Suppose you want to find all email addresses in a users table that exist more than once:

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



you can see more information about removing duplicate rows from this microsoft article
How to remove duplicate rows from a table in SQL Server

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