oracle删除重复数据，只保留一条

比如，某个表要按照id和name重复，就算重复数据

delete from 表名 where rowid not in (select min(rowid) from 表名 group by id,name);
commit;

如果以id，name和grade重复算作重复数据

delete from 表名 where rowid not in (select min(rowid) from 表名 group by id,name,grade);
commit;

注意  min也可以换成max