符合条件进行更新操作，不符合则进行插入操作．
merge into myd_nsrdt n using (select ‘9‘as mydtmid,‘1‘as tmtype,‘370200123456788‘as nsrsbh,‘‘ as nsrmc, ‘sn‘ as region,4 as pf,‘‘as yj,‘18888888888‘ as phone,‘18888888888‘ as nowphone,sysdate as addtime from dual) m on(n.mydtmid=m.mydtmid and n.nsrsbh=m.nsrsbh) when matched then update set n.pf=m.pf,n.yj=m.yj where n.mydtmid=m.mydtmid and n.nsrsbh=m.nsrsbh when not matched then insert values(seq_myd.nextval,m.mydtmid,m.tmtype,m.nsrsbh,m.nsrmc,m.region,m.pf,m.yj,m.phone,m.nowphone,m.addtime)
原文：http://www.cnblogs.com/yshyee/p/4529619.html