查找重复数据

create table AAAA
(
NAME VARCHAR2(10),
SEX VARCHAR2(10),
AGE VARCHAR2(10)
);

insert into AAAA(name,sex,age) values('1','1','1');
insert into AAAA(name,sex,age) values('2','2','2');
insert into AAAA(name,sex,age) values('2','2','2');
insert into AAAA(name,sex,age) values('3','3','3');

--查找重复行：
select *
from AAAA a
where (a.NAME, a.SEX, a.AGE) in
(select NAME, SEX, AGE
from AAAA
group by NAME, SEX, AGE
having count(1) > 1);

--1、查找表中多余的重复记录，重复记录是根据单个字段（peopleId）来判断
select * from AAAA
where NAME in (select NAME from AAAA group by NAME having count(NAME) > 1);

--2、删除表中多余的重复记录，重复记录是根据单个字段（peopleId）来判断，只留有rowid最小的记录
delete from AAAA
where NAME in (select NAME from AAAA group by NAME having count(NAME) > 1)
and rowid not in (select min(rowid) from AAAA group by NAME having count(NAME )>1);

--3、查找表中多余的重复记录（多个字段）
select * from AAAA a
where (a.NAME,a.SEX) in (select NAME,SEX from AAAA group by NAME,SEX having count(*) > 1);

--4、删除表中多余的重复记录（多个字段），只留有rowid最小的记录
delete from AAAA a
where (a.NAME,a.SEX) in (select NAME,SEX from AAAA group by NAME,SEX having count(*) > 1)
and rowid not in (select min(rowid) from AAAA group by NAME,SEX having count(*)>1);

--5、查找表中多余的重复记录（多个字段），不包含rowid最小的记录
select * from AAAA a
where (a.NAME,a.SEX) in (select NAME,SEX from AAAA group by NAME,SEX having count(*) > 1)
and rowid not in (select min(rowid) from AAAA group by NAME,SEX having count(*)>1);