Oracle 查询并删除重复记录的SQL语句

1、查找表中多余的重复记录，重复记录是根据单个字段（product_id）来判断

select * from p_category_product
where product_id in (select product_id from p_category_product group by product_id having count(product_id) > 1) order by product_id,p_category_id

2、查找表中多余的重复记录（多个字段）

select * from p_category_product
where (product_id,p_category_id) in 
(select product_id,p_category_id from p_category_product group by product_id,p_category_id having count(*) > 1)
order by product_id,p_category_id