删除重复记录可以:如果有ID字段,就是具有唯一性的字段delect table where id not in ( select max(id) from table group by col1,col2,col3... ) group by 子句后跟的字段就是你用来判断重复的条件,如只有col1,那么只要col1字段内容相同即表示记录相同。2,如果是判断所有字段也可以这样 select * into #aa from table group by id1,id2,.... delete table insert into table select * from #aa3,没有ID的情况select identity(int,1,1) as id,* into #temp from tabel delect # where id not in ( select max(id) from # group by col1,col2,col3...) delect table inset into table(...) select ..... from #temp col1+','+col2+','...col5 联合主键 select * from table where col1+','+col2+','...col5 in ( select max(col1+','+col2+','...col5) from table where having count(*)>1 group by col1,col2,col3,col4 ) group by 子句后跟的字段就是你用来判断重复的条件,如只有col1,那么只要col1字段内容相同即表示记录相同。2, select identity(int,1,1) as id,* into #temp from tabel select * from #temp where id in ( select max(id) from #emp where having count(*)>1 group by col1,col2,col3...)
如果重复的字段是f1 select * from table t1 where (select count(t2.f1) from table t2 group by t2.f1 where t2.f1 = t1.f1) > 1
select colname,count(colname) from tablename group by colname having count(colname) > 1
是SQL SERVER 2K? 我可以给你一个数据冗余检查程序,多种灵活处理方式,包括保留一条冗余纪录等,但是因为是在工作时间内开发的,所以只能给编译好的可运行程序,需要给我发邮件: [email protected]
select 重复字段,count(*) from table group by 重复字段 having count(*)>1------------------------ 已测试
)
group by 子句后跟的字段就是你用来判断重复的条件,如只有col1,那么只要col1字段内容相同即表示记录相同。2,如果是判断所有字段也可以这样
select * into #aa from table group by id1,id2,....
delete table
insert into table
select * from #aa3,没有ID的情况select identity(int,1,1) as id,* into #temp from tabel
delect # where id not in (
select max(id) from # group by col1,col2,col3...)
delect table
inset into table(...)
select ..... from #temp
col1+','+col2+','...col5 联合主键
select * from table where col1+','+col2+','...col5 in ( select max(col1+','+col2+','...col5) from table
where having count(*)>1
group by col1,col2,col3,col4
)
group by 子句后跟的字段就是你用来判断重复的条件,如只有col1,那么只要col1字段内容相同即表示记录相同。2,
select identity(int,1,1) as id,* into #temp from tabel
select * from #temp where id in (
select max(id) from #emp where having count(*)>1 group by col1,col2,col3...)
select * from table t1 where (select count(t2.f1) from table t2 group by t2.f1 where t2.f1 = t1.f1) > 1
我可以给你一个数据冗余检查程序,多种灵活处理方式,包括保留一条冗余纪录等,但是因为是在工作时间内开发的,所以只能给编译好的可运行程序,需要给我发邮件:
[email protected]
group by 重复字段
having count(*)>1------------------------
已测试