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񡜧TBL_Info
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    infoId int
    title  varchar(20)
    Content  text
    byUser  varchar(20)
    createTime datetime
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--1
--1.1Ïàͬʱ±£Áô×îСµÄinfoId
delete TBL_Info from TBL_Info t where infoId not in (select min(id) from infoId where title = t.title and Content = t.Content and byUser = t.byUser and createTime = t.createTime)
--1.1Ïàͬʱ±£Áô×î´óµÄinfoId
delete TBL_Info from TBL_Info t where infoId not in (select max(id) from infoId where title = t.title and Content = t.Content and byUser = t.byUser and createTime = t.createTime)
--2
delete from TBL_Info where title in (select title from TBL_Info group by title having count(1) > 1)
--3
select title , count(1) from TBL_Info group by title
select title , count(*) from TBL_Info group by title
select title , count(title) from TBL_Info group by title
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select * from people
where peopleId in (select  peopleId  from  people  group  by  peopleId  having  count(peopleId) > 1)
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delete from people
where peopleId  in (select  peopleId  from people  group  by  peopleId  having  count(peopleId) > 1)
and rowid not in (select min(rowid) from  people  group by peopleId  having count(peopleId )>1)
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select * from vitae a
where (a.peopleId,a.seq) in  (select peopleId,seq from vitae group by peopleId,seq  having count(*) > 1)
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