Oracle 中去掉重复项问题,两种方式对比 那个更快 还有没有更快的 求指导
安得权 2015-08-28 03:59:36 语句1:
delete from temp_goods_201503200331 where rowid not in (select min(rowid) from temp_goods_201503200331 group by HSCODE,NAME having count(name)>=1)
语句2:
DELETE FROM temp_goods_201503200331 d
WHERE rowid >
( SELECT min(rowid)
FROM temp_goods_201503200331 t
WHERE
t.hscode = d.Hscode and t.name=d.name
)