oracle update 多表关联

update多表关联示例：

Sql代码

1. updateAaseta.route=
2. (selectb.routefromBbwherea.orgn=b.orgnanda.dest=b.dest)
3. whereexists
4. (select*fromBbwhereb.orgn=a.orgnandb.dest=a.dest);

update 超过2个值

Sql代码

1. updatecustomersa
2. set(city_name,customer_type)=(selectb.city_name,b.customer_type
3. fromtmp_cust_cityb
4. whereb.customer_id=a.customer_id)
5. whereexists(select1
6. fromtmp_cust_cityb
7. whereb.customer_id=a.customer_id)