ORA-00979 not a group by expression

Question

I am getting ORA-00979 with the following query:

SELECT cr.review_sk, cr.cs_sk, cr.full_name,
tolist(to_char(cf.fact_date, \'mm/dd/yyyy\')) \"appt\",
cs.cs_i         


        

Answer 1

The group by is used to aggregate some data, depending on the aggregate function, and other than that you need to put column or columns to which you need the grouping.

for example:

select d.deptno, max(e.sal) 
from emp e, dept d
where e.deptno = d.deptno
group by d.deptno;

This will result in the departments maximum salary.

Now if we omit the d.deptno from group by clause it will give the same error.