Finding duplicate records in mysql
We have two tables epaper and epaper_pages. Every epaper_pages table recrod has a specific page number assigned. We have to check that each epaper_pages table record has no epaper_page_no duplicate number.
SELECT ( SELECT COUNT(*) FROM epaper_pages WHERE epaper_pages.epaper_id = epaper.id GROUP BY epaper_pages.epaper_page_no HAVING COUNT(*) > 1 ) AS dublicate_count, epaper.* FROM epaper ORDER BY dublicate_count DESC