我有两个表
A表 B表tempid name pid name tempid
-------------------- ----------------------------
12 xb001 a 12
13 xb002 b 13
14 xb003 d 14
15 xb004 e 15我想将A表中的tempid ,name字段的值更新为B表中 PID,name的值,请教如何作到。由于数据量很大,我的做法实在是太慢了,求教高手多谢了
A表 B表tempid name pid name tempid
-------------------- ----------------------------
12 xb001 a 12
13 xb002 b 13
14 xb003 d 14
15 xb004 e 15我想将A表中的tempid ,name字段的值更新为B表中 PID,name的值,请教如何作到。由于数据量很大,我的做法实在是太慢了,求教高手多谢了
set name = b.name
from a , b
where a.tempid = b.tempid
update a
set name = b.name ,
tempid = b.pid
from a , b
where a.tempid = b.tempid
a
set
name = b.name
from
a , b
where
a.tempid = b.tempid
---------- ----------
xb001 a
xb002 b
xb003 d
xb004 e(所影响的行数为 4 行)
create table b(pid varchar(10), name varchar(10), tempid varchar(10))
insert into a (tempid) values(12)
insert into a (tempid) values(13)
insert into a (tempid) values(14)
insert into a (tempid) values(15)insert into b values('xb001' , 'a' , 12 )
insert into b values('xb002' , 'b' , 13 )
insert into b values('xb003' , 'd' , 14 )
insert into b values('xb004' , 'e' , 15 )update a
set name = b.name ,
tempid = b.pid
from a , b
where a.tempid = b.tempid select * from adrop table a , b