不把表发上来，起码把完整的命令发上来呀。试试下面的命令。
select a.* from  表1 a , 表2, 表3 c into dbf  结果 where  a.h1=b.h1 and a.h2=b.h2 and a.h3.=b.h3 and a.h1=c.h1 and a.h2=c.h2 and a.h3.=c.h3 and c.h1=b.h1 and c.h2=b.h2 and c.h3.=b.h3

没有表如何解决问题

create cursor t1 (h1 n(1), h2 n(1), h3 n(1))
insert into t1 values (0, 1, 2)
insert into t1 values (1, 2, 3)
insert into t1 values (2, 3, 4)
create cursor t2 (h1 n(1), h2 n(1), h3 n(1))
insert into t2 values (2, 3, 4)
insert into t2 values (0, 1, 2)
insert into t2 values (2, 3, 1)
create cursor t3 (h1 n(1), h2 n(1), h3 n(1))
insert into t3 values (2, 3, 4)
insert into t3 values (3, 4, 5)
insert into t3 values (0, 1, 2)

select t1.h1, t1.h2, t1.h3 from t1, t2, t3 where ;
str(t1.h1) + str(t1.h2) + str(t1.h3) == str(t2.h1) + str(t2.h2) + str(t2.h3) and ;
str(t1.h1) + str(t1.h2) + str(t1.h3) == str(t3.h1) + str(t3.h2) + str(t3.h3) order by t1.h1, t1.h2, t1.h3

这几天出门了。才回来。非常感谢您的帮助。以后有问题还得请教您。

诚意不足，你既然来请教，就应当拿出数据啊。。。