select T1.a列 FROM T1 LEFT JOIN T2 ON T1.a列 = T2.a列 AND T1.b列 = T2.b列 WHERE T2.a列 IS NULL
是的,只想想得到T1表a列的 k0001 k0003
k0001 w1 k0001 w1 k0001 w2 k0001 w2 k0002 w8 k0002 w8 k0002 w9 k0003 w1 k0003 w1 k0004 w1 k0004 w2select T1.a from T1,T2 where T1.a=T2.a and T1.b=T2.b
create table T1 ( a varchar(10), b varchar(2) )create table T2 ( a varchar(10), b varchar(2) )insert T1 select 'k0001','w1' insert T1 select 'k0001','w2' insert T1 select 'k0002','w8' insert T1 select 'k0002','w9' insert T1 select 'k0003','w1' insert T1 select 'k0004','w1' insert T1 select 'k0004','w2' insert T2 select 'k0001','w1' insert T2 select 'k0001','w2' insert T2 select 'k0002','w8' insert T2 select 'k0003','w1' select DISTINCT T2.a from T2 where T2.a not in ( select T.a from (select T1.a as a,T2.a as b from T1 left join T2 on T1.a=T2.a and T1.b=T2.b) T where T.b is null )
T1.a列
FROM
T1
LEFT JOIN
T2
ON
T1.a列 = T2.a列 AND
T1.b列 = T2.b列
WHERE
T2.a列 IS NULL
k0001
k0003
k0001 w2 k0001 w2
k0002 w8 k0002 w8
k0002 w9 k0003 w1
k0003 w1
k0004 w1
k0004 w2select T1.a
from T1,T2
where T1.a=T2.a
and T1.b=T2.b
create table T1
(
a varchar(10),
b varchar(2)
)create table T2
(
a varchar(10),
b varchar(2)
)insert T1 select 'k0001','w1'
insert T1 select 'k0001','w2'
insert T1 select 'k0002','w8'
insert T1 select 'k0002','w9'
insert T1 select 'k0003','w1'
insert T1 select 'k0004','w1'
insert T1 select 'k0004','w2'
insert T2 select 'k0001','w1'
insert T2 select 'k0001','w2'
insert T2 select 'k0002','w8'
insert T2 select 'k0003','w1'
select DISTINCT T2.a
from T2
where T2.a not in
(
select T.a from (select T1.a as a,T2.a as b from T1 left join T2 on T1.a=T2.a and T1.b=T2.b) T where T.b is null
)
谢谢啦,