TABLE 1
ID C1 C2 C3
1 XX YY ZZ
2 XX1 YY1 ZZ1
3 XX2 YY2 ZZ2
TABLE 2 把C1C2C3 通过表1 放进去
ID C1 C2 C3
1
2
3
如何用 update from啊
我写的是
update table2 set c1=(select top 1 c1 from table1 where id =table2.id),
c2=(select top 1 c2 from table1 where id =table2.id)
c3=(select top 1 c3 from table1 where id =table2.id)
这种方法很死,而且没有效率
我想用
update table2
set c1=t.c1,c2=t.c2,c3=t.c3
from (select top 1 c1,c2,c3 from table1 where id=table1.id ) t
为什么不行。报错。。。
------最佳解决方案--------------------
UPDATE b
SET b.c1 = a.c1 ,
b.c2 = a.c2 ,
b.c3 = a.c3
FROM TABLE1 a
INNER JOIN TABLE2 b ON a.id = b.id
------其他解决方案--------------------
update table2 set C1=b.c1,c2=b.c2,c3=b.c3
from table2 as a inner join table1 as b on a.id=b.id
------其他解决方案--------------------
update table2
set c1=t.c1,c2=t.c2,c3=t.c3
from (select top 1 c1,c2,c3 from table1 where id=table1.id ) t
此句错误在于,select的值不确定,换句话讲范围不定啊。你要找一个唯一确定的值。
------其他解决方案--------------------
update table_2 set c1=a.c1,c2 = a.c2,b.c3 = a.c3
from table_1 a
where table_2.id=a.id
------其他解决方案--------------------
update table_2 set c1=a.c1,c2 = a.c2,c3 = a.c3
from table_1 a
where table_2.id=a.id
写错一个字母!
------其他解决方案--------------------
update table2 set C1=b.c1,c2=b.c2,c3=b.c3
from table2 as a inner join table1 as b on a.id=b.id
------其他解决方案--------------------
这上面写的方法我都试了,都不行呀!
------其他解决方案--------------------
这个可以的,不知道你错在哪一步!
create table a
(
id int not null,
a varchar(50) null,
b varchar(50) null,
c varchar(50) null,
d varchar(50) null
)
create table b