SQL Query To Find Duplicate Records

Chapter: SQL Commands Last Updated: 17-04-2023 13:33:56 UTC

Program:

            /* ............... START ............... */
                
SELECT column1, column2, COUNT(*)
FROM table_name
GROUP BY column1, column2
HAVING COUNT(*) > 1;

                /* ............... END ............... */
        

Notes:

• To find duplicate records in a SQL table, you can use the GROUP BY clause along with the HAVING clause to filter out the records that have more than one occurrence.
• This query selects the columns you want to check for duplicates (replace column1 and column2 with the actual names of the columns), groups the records by the selected columns, and then counts the number of occurrences for each group. Finally, it filters out the groups that have more than one occurrence using the HAVING clause.
• This will return all the duplicate records in the table based on the selected columns. If you want to delete the duplicate records, you can modify the query to use a DELETE statement instead of a SELECT statement.

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