oracle中如何选择计数

Question

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如何计算job_title的工资？

我尝试过这样的编码，但结果错误 这是我的代码

select a.job_id,a.job_title,avg(b.salary) gaji_rata_rata 
from jobs a, employees b where a.job_id=b.job_id  order by job_id;

Answer 1

使用聚合函数时需要分组

select a.job_id,a.job_title,avg(b.salary) gaji_rata_rata 
from jobs a, employees b 
where a.job_id=b.job_id  
group by  a.job_id,a.job_title
order by job_id;