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How to find duplicate records in a table?

How to find the duplicate records in a table?

Query:

Simple Table

SELECT c1, c2, ... ,cn, count(*)
FROM TableName
GROUP BY c1, c2,..., cn
HAVING count(*) > 1;

Table with Joins:

SELECT c1, c2, ... ,cn, count(*)
FROM TableName1
INNER JOIN TableName2 on TableName1.ColName=TableName2.ColName

GROUP BY c1, c2,..., cn HAVING count(*) > 1;



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