sql - ORA-00979 not a group by expression -

i getting ora-00979 following query:

select cr.review_sk, cr.cs_sk, cr.full_name, tolist(to_char(cf.fact_date, 'mm/dd/yyyy')) "appt", cs.cs_id, cr.tracking_number review cr, cs, fact cf cr.cs_sk = cs.cs_sk , upper(cs.cs_id) '%' || upper(i_cs_id) || '%' , row_delete_date_time null , cr.review_sk = cf.review_wk (+) , cr.fact_type_code (+) = 183050 group cr.review_sk, cr.cs_sk, cf.fact_date, cr.tracking_number order cs.cs_id, cr.full_name; 

i couldn't find examples had both group , order clauses in same query. tried removing each field group 1 @ time, still getting same error.

you must put columns of select in group by or use functions on them compress results single value (like min, max or sum).

a simple example understand why happens: imagine have database this:

foo bar 0   0   b 

and run select * table group foo. means database must return single row result first column 0 fulfill group by there 2 values of bar chose from. result expect - a or b? or should database return more 1 row, violating contract of group by?