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 people
where peopleId in
(
select peopleId
from people
group by peopleId
having count(peopleId) > 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 people
where peopleName in
(
select peopleName
from people
group by peopleName
having count(peopleName) > 1
)
and
peopleId not in
(
select min(peopleId)
from people
group by peopleName
having count(peopleName)>1
)
3、查找表中多余的重复记录(多个字段)
select *
from vitae a
where (a.peopleId,a.seq)
in
(
select peopleId,seq
from vitae
group by peopleId,seq
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 vitae a
where (a.peopleId,a.seq)
in
(
select peopleId,seq
from vitae
group by peopleId,seq
having count() > 1
)
and
rowid not in
(
select min(rowid)
from vitae
group by peopleId,seq
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 vitae a
where (a.peopleId,a.seq)
in
(
select peopleId,seq
from vitae
group by peopleId,seq
having count() > 1
)
and
rowid not in
(
select min(rowid)
from vitae
group by peopleId,seq
having count()>1
)
6.消除一个字段的左边的第一位:
update tableName
set [Title]=Right([Title],(len([Title])-1))
where Title like ‘村%’
7.消除一个字段的右边的第一位:
update tableName
set [Title]=left([Title],(len([Title])-1))
where Title like ‘%村’
8.假删除表中多余的重复记录(多个字段),不包含rowid最小的记录
update vitae
set ispass=-1
where peopleId
in
(
select peopleId
from vitae
group by peopleId,seq
having count() > 1
)
and
seq in
(
select seq
from vitae
group by peopleId,seq
having count() > 1
)
and
rowid not in
(
select min(rowid)
from vitae
group by peopleId,seq
having count(*)>1
)