现象
- 在group by 和order by配合使用执行oracle数据库查询时,出现异常
原SQL语句
select SDEPARTMENT, SCONTRACT_NAME, avg(DCONTRACT_VALUE) DCONTRACT_VALUE
from HY_PROJECT_ACCOUNTBOOK
where SPROJECT_ID = 'EERIU651453'
group by SCONTRACT_NAME, SDEPARTMENT
order by INUM desc;
异常
ORA-00979: 不是 GROUP BY 表达式
00979. 00000 - "not a GROUP BY expression"
原因
-
order by 排序的对象是group by 分组之后的数据,很显然没有INUM字段
-
假设没有order by 排序的需求
select SDEPARTMENT, SCONTRACT_NAME, avg(DCONTRACT_VALUE) DCONTRACT_VALUE
from HY_PROJECT_ACCOUNTBOOK
where SPROJECT_ID = 'EERIU651453'
group by SCONTRACT_NAME, SDEPARTMENT;
- 新增按INUM排序的需求(group by 字句中新增INUM字段)
select min(INUM) INUM, SDEPARTMENT, SCONTRACT_NAME, avg(DCONTRACT_VALUE) DCONTRACT_VALUE
from HY_PROJECT_ACCOUNTBOOK
where SPROJECT_ID = 'EERIU651453'
group by SCONTRACT_NAME, SDEPARTMENT
order by INUM desc;