sql语句之左连结

select
t.BUSINESS,
t.CONTRACTNO,
t.HOUSESID,
t.DEALER,
h.ADDRESS,
c.APPROVEDATE,
c.REALPRICE,
c.CUSTOMERCOMMISSION
from TRANSATION.CONTRACT_INFO t
left join HOUSES.HB_HOUSE_RESOURCE h on t.HOUSESID=h.ID
left join TRANSATION.CONTRACT c on t.CONTRACTNO=c.CONTRACTNO where t.DEALER!=0 and t.CUSTID