多表批量update

 update ROYWSQ a set (a.ROYWSQ_YHK) =

--使用子查询，保证子查询返回一行！

(select  b.ROJKHX_HXJE from ROJKHX b,ROBXDJ

 where b.ROJKHX_SQDJ = a.ROYWSQ_NM and ROYWSQ_YHK is null and ROJKHX_SQDJ = ROYWSQ_NM and ROBXDJ_NM= ROJKHX_HXDJ  --148

 and ROBXDJ_ZT = '6')

--  下面是批量更新的内容

 where ROYWSQ_NM in
 (
select ROJKHX_SQDJ
from ROYWSQ,ROJKHX,ROBXDJ
 where ROYWSQ_YHK is null and ROJKHX_SQDJ = ROYWSQ_NM and ROBXDJ_NM= ROJKHX_HXDJ  --148
 and ROBXDJ_ZT = '6'
 )