想查询两个数据相减的结果,但是数据读不出来,一直显示正在加载数据请问这是什么原因?代码如下select a.bic_mzxnjg,a.mmzecfl1,a.khfl1_txt,a.mmzecfl2,a.khfl2_txt,a.mmm_ypdl,a.mmmbwcs2,a.jsl-b.jhl as kcl from(SELECT bic_mzxnjg,mmzecfl1,khfl1_txt,mmzecfl2,khfl2_txt,mmm_ypdl,mmmbwcs2,sum(msdjsqty)/count(doc_num) AS jsl,sum(subtot_oc1)/count(doc_num)AS jsje from app_yc.yc_kcl_orc where jsdat <= '${tjdate}' /*结算前台查询日期示例, '2022-12-20'*/GROUP BY bic_mzxnjg,mmzecfl1,khfl1_txt,mmzecfl2,khfl2_txt,mmm_ypdl,mmmbwcs2)a,(SELECT bic_mzxnjg,mmzecfl1,khfl1_txt,mmzecfl2,khfl2_txt,mmm_ypdl,mmmbwcs2,sum(nvl(act_dl_qty,0)) AS jhl from app_yc.yc_kcl_orc where jsdat <= '${tjdate}' and jhdat <= '${tjdate}'/*交货前台查询日期示例, '2022-12-20'*/GROUP BY bic_mzxnjg,mmzecfl1,khfl1_txt,mmzecfl2,khfl2_txt,mmm_ypdl,mmmbwcs2)b