update 多表链接

update A
set A.shl = A.shl - B.shl 
from retmxls A,daysphz B
where A.spid = B.spid and 
A.fdbs = B.fdbs and 
A.rq = B.rq and
A.ontime > '17:37:18' and 
A.shky = '002' and 
A.fdbs = 'HKD'