sql的合计方法？

SQL code

SELECT  v_qyfhqd.Fhqdh ,           v_qyfhqd.hwbh ,           v_qyfhqd.Clbh ,           v_qyfhqd.Jydbh ,           v_qyfhqd.Fhsl ,           v_qyfhqd.Fhzl ,           v_qyfhqd.Fhtj ,           v_qyfhqd.Fszbm ,           v_qyfhqd.Other ,           v_qyfhqd.lwfy ,           v_qyfhqd.Sxhh ,           v_qyfhqd.Hwmc ,           v_qyfhqd.Hwlx ,           v_qyfhqd.Fhzt ,           v_qyfhqd.dzzbm ,           v_qyfhqd.qdjh ,           v_qyfhqd.Fhrxm ,           v_qyfhqd.Fhrdh ,           v_qyfhqd.Shrxm ,           v_qyfhqd.Shrdh ,           v_qyfhqd.zyfs ,           v_qyfhqd.Thfs ,           v_qyfhqd.Sdzbm ,           v_qyfhqd.cyf ,           v_qyfhqd.Zbxf ,           v_qyfhqd.Jjfy ,           v_qyfhqd.Zdzf ,           v_qyfhqd.Dshk ,           v_qyfhqd.Hdfk ,           v_qyfhqd.Yjyfhj ,           v_qyfhqd.Sqke ,           v_qyfhqd.Hkze ,           v_qyfhqd.Kcsj ,           v_qyfhqd.fhy ,           v_qyfhqd.zcy ,           v_qyfhqd.gsjbr ,           v_qyfhqd.Other_b ,           v_qyfhqd.jsyxm ,           v_qyfhqd.Sfzh ,           v_qyfhqd.Scdh ,           v_qyfhqd.Zdzbm ,           v_qyfhqd.tyfz ,           v_qyfhqd.other_c ,           v_qyfhqd.Sfjj ,           v_qyfhqd.Zyf,           sum(zyf)  as zyff,           v_qyfhqd.fkfs ,           v_qyfhqd.clyf ,           v_qyfhqd.Fgsbm             FROM v_qyfhqd              WHERE ( v_qyfhqd.Fhqdh ='101201201280001' )          group by Fhqdh,hwbh,clbh,jydbh,fhsl,fhzl,fhtj,fszbm,other,lwfy,sxhh,hwmc,hwlx,fhzt,dzzbm,qdjh,fhrxm,        fhrdh,shrxm,shrdh,zyfs,thfs,sdzbm,cyf,zbxf,jjfy,zdzf,dshk,hdfk,yjyfhj,sqke,hkze,kcsj,fhy,zcy,        gsjbr,other_b,jsyxm,sfzh,scdh,zdzbm,tyfz,other_c,sfjj,clyf,fgsbm,fkfs,zyf

结果如下
0246246现金0101
NULL438438到付0101
现在只要合计付款方式为到付的运费，如果是现金和欠款的不要合计进来
要得到的结果为
zyff
438

[解决办法]

SQL code

--在你的结果上嵌套一下  select sum(zyff) from (你的语句) aa where colname='到付'