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【DM版本】:dm8
【操作系统】：centos7
【CPU】:x86
【问题描述】*：查询语句执行报错，显示嵌套分组函数没有 GROUP BY,其中GROUP_OPT_FLAG已经设置为了53

语句如下：
select nvl(sum(nvl(a.bill_amount, 0) -
(nvl(a.third_party_pay_amount, 0) + SUM(nvl(commer_insur_pay_amt,0)) +
nvl(a.other_amount8, 0) + nvl(a.deduct_amount, 0) +
nvl(a.self_charge_amount, 0) +
nvl(a.other_amount2, 0) +
nvl(a.unreasonable_amount, 0)) -
nvl(a.other_amount3, 0)),
0)
from gcm_medical_bill_info a
where a.is_valid = 'Y'
and a.other_amount7 <= a.medical_pay_top_level
and a.other_amount7 >= a.medical_pay_low_level
and a.claim_no = p_claim_no;