How do you find duplicate entries in a SQL table

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How do you find duplicate entries in a SQL table

cuseman03

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Points: 194
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December 17, 2019 at 11:12 pm

#3708656

Hi,
while I don't yet have any code to show I am trying to find duplicates in a table. So I revert to excel logic here in that if I were working in that however many columns I had, I would take the values from every cell in a row and I would concatenate to produce a unique value. Then I would identify duplicates. How do you do this in SQL? Having count >1 is part of it but how do you ensure the check is done on a unique concatenation of values

Thanks!

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Joe Torre SSChampion Points: 10248 More actions · Answer 1

If I have a table:

CREATE TABLE EMP
   (
     ID int
   , NAME varchar(50)
   , TITLE varchar (20)
   );
GO
INSERT INTO EMP
VALUES
     (1, 'Joe Cool', 'CEO')
   , (1, 'Joe Cool', 'CEO')
   . (2. . 'Snoopy', .'pet');
GO
SELECT ID, NAME, TITLE
FROM EMP
GROUP BY ID, NAME, TITLE
HAVING COUNT(*)>1;