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

Same error also come when UPPER or LOWER keyword not used in both place in select expression and group by expression .

Wrong :-

select a , count(*) from my_table group by UPPER(a) .

Right :-

select UPPER(a) , count(*) from my_table group by UPPER(a) .