How to find complete duplicate rows in MySQL table?

Question

MySQL

There is a table with about half a million rows of records in MySQL. The table has about 10 columns, the first id is the rest of different data types. How can you find absolute duplicate rows (not counting id's) among all this data?

Answer 1

//f1, f2 - все поля  по которым ищем дубликаты
SELECT f1, f2, COUNT( f1) AS cnt
FROM table
GROUP BY f1, f2
HAVING (cnt > 1)

Answer 2

Calculate the hash of the sum of the string representations of the delimited columns without ID.