update a set code=b.code from cn..yyy as a,kn..xxx as b where a.id=b.id
1、id是主键吗? 2、id上有索引吗?
update a set code=b.code from cn..yyy as a,kn..xxx as b where a.id=b.id
语句没错,只有2万多条,把id限制一下,分批试试,看看问题在什么地方 如: update cn..yyy set code=b.code from cn..yyy as a,kn..xxx as b where a.id=b.id and a.id<5000update cn..yyy set code=b.code from cn..yyy as a,kn..xxx as b where a.id=b.id and a.id>=5000 and a.id<10000
1.没有错误 2.慢,要看服务器配置 3.建议改为 update cn..yyy set code=b.code from cn..yyy as a inner join kn..xxx as b on a.id=b.id
set code=b.code
from cn..yyy as a,kn..xxx as b
where a.id=b.id
2、id上有索引吗?
set code=b.code from cn..yyy as a,kn..xxx as b
where a.id=b.id
如:
update cn..yyy
set code=b.code from cn..yyy as a,kn..xxx as b
where a.id=b.id and a.id<5000update cn..yyy
set code=b.code from cn..yyy as a,kn..xxx as b
where a.id=b.id and a.id>=5000 and a.id<10000
2.慢,要看服务器配置
3.建议改为
update cn..yyy
set code=b.code from cn..yyy as a inner join kn..xxx as b
on a.id=b.id