Delete duplicate simple product with same attribute from a configurable product in CSV

Import configurable csv to a mysql database table then try to use bellow sql query which give you the duplicate simple product with same attribute values.

delete from `table_1` where sku in ( select sku from ( SELECT `sku` FROM `table_1` Group BY `orientatie`,`material`,`papier`,`paginas`,`paper_type_cover`,`veredeling_omslag`,`levertijd`,`aantal` Having COUNT(*) > 1 ) t )