How Can I Identify and Retrieve Only Duplicate Records Across Multiple Fields in SQL?

Find duplicate records based on multiple fields

Identifying duplicate records in your database is critical for data integrity and analysis. A common need is to find duplicates across multiple fields and retrieve details beyond the first record.

To do this, you can use the following SQL statement:

select field1, field2, field3, count(*)
from table_name
group by field1, field2, field3
having count(*) > 1;

This query will return fields with corresponding counts, allowing you to identify repeating combinations. However, it does not exclude the first occurrence of each duplicate.

To retrieve only subsequent occurrences of duplicates, you can refer to this knowledge base article: https://www.php.cn/link/97fa70856aa8095cb1a6c7343a84bd85.

Before applying the above method, the criteria for determining the "first row" must be defined. If you have sample data, providing it will help improve the method and provide more accurate responses.

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