How Do I Select Duplicate Records from a Database Table

This T-SQL snippet allows you to select duplicate records from a database table. The example assumes that the column Id is used to determine whether a record has a duplicate. If multiple columns determine whether a record has a duplicate or not, simply expand the SELECT list and the GROUP BY clause.
SELECT
    Id
FROM
    aTable
GROUP BY
    Id
HAVING
    (COUNT(Id) > 1)

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Doc ID 218
Full URL https://imar.spaanjaars.com/218/how-do-i-select-duplicate-records-from-a-database-table
Short cut https://imar.spaanjaars.com/218/
Written by Imar Spaanjaars
Date Posted 11/08/2003 21:33
Date Last Updated 11/02/2020 16:29
Date Last Reviewed 12/06/2006 18:19

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