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ÁÐ1 ÁÐ2
A B
B A
C D
E F
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select * from ±í where ÁÐ1=ÁÐ2
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SQL code:
create table tb(c1 varchar(10),c2 varchar(10))
insert into tb values('A' , 'B')
insert into tb values('B' , 'A')
insert into tb values('C' , 'D')
insert into tb values('E' , 'F')
go
select m.* from tb m ,tb n where m.c1 = n.c2 and m.c2 = n.c1
drop table tb
/*
c1 c2
---------- ----------
A B
B A
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*/
ÕâÊÇÁ½¸ö±íÂð,û̫¿´Ã÷°×ѽ
select * from ±í1,±í2 where ±í1.A=±í2.B and ±í1.B=±í2.A?
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SQL code:
create table tb(c1 varchar(10),c2 varchar(10))
insert into tb values('A' , 'B')
insert into tb values('B' , 'A')
insert into tb values('C' , 'D')
insert into tb values('E' , 'F')
select *
from tb a
where exists(select * from tb where a.c1=c2 and a.c2=c1 )
/*
c1 c2
---------- ---
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