请教一下各位大牛，这段sql该如何优化？（附执行计划）

select t3.*, nvl(t5.sum_kcsl, 0) sum_kcsl, nvl(t5.sum_clsl, 0) sum_clsl
  from (select t2.fydm,
               t2.mc,
               t2.gg,
               t2.kfbh,
               t2.pch,
               t2.sfkccl,
               t2.dw,
               t2.jx,
               t2.dj,
               sum(t2.sl) as zsl,
               sum(t2.je) as zje
          from zl_zydj t, fy_fymx t2
         where t2.jzxh = t.jzxh
           and t2.zhbh = t.zhbh
           and t2.zxbz = '0'
           and (t2.fylb = '0' or t2.wzlb = '1')
           and t2.kfbh = '103116'
           and t2.zhbh = '3305230028'
           and t2.fyzt = '0'
           and t2.jzlb = '1'
           and t.zyzt <> '4'
         group by t2.fydm,
                  t2.mc,
                  t2.gg,
                  t2.kfbh,
                  t2.pch,
                  t2.sfkccl,
                  t2.dw,
                  t2.jx,
                  t2.dj
         ) t3
  left join (select t4.wzbh,
                    t4.kfbh,
                    t4.pch,
                    sum(t4.kcsl) as sum_kcsl,
                    sum(t4.clsl) as sum_clsl
               from kc_pckctz t4
              where 1 = 1
                and t4.kfbh = '103116'
                and t4.zxbz = '0'
                and t4.sfty = '0'
                and t4.zhbh = '3305230028'
                and t4.yxqz >= '20170214'
                and (t4.kcsl <> 0.0 or t4.clsl <> 0.0)
              group by t4.wzbh, t4.kfbh, t4.pch) t5
    on t3.pch = t5.pch
   and t3.fydm = t5.wzbh
   and t3.kfbh = t5.kfbh
   and ((decode(t3.pch, null, 1, 0)) = 1 or
       (t5.sum_kcsl <> 0 or t5.sum_clsl <> 0))下面是执行计划：