How to select and move rows with duplicate key value to a clean table?

Question

linux

There is a table:

Код;Остаток
00000406;15
00000803;6
00000745;3
00000406; 7

Tell me, please, how can I select rows with a duplicate value of the "Code" field and copy them into a clean table?

Код;Остаток
00000406; 7

Answer 1

INSERT INTO new_table (code, amount)
(SELECT code, amount FROM tabla GROUP BY code HAVING count(*) > 1)