Find duplicate records in MySQL - หาเรคคอร์ดที่ซ้ำกันใน MySQL

Find duplicate records in MySQL

Do a SELECT with a GROUP BY clause. Let's say name is the column you want to find duplicates in:

SELECT name, COUNT(*) c FROM table GROUP BY name HAVING c > 1;

This will return a result with the name value in the first column, and a count of how many times that value appears in the second.

Credit : http://stackoverflow.com/questions/688549/finding-duplicate-values-in-mysql