CodeListing 3: Explain plan report on new (BIG) EMP query 

Id      Operation            Name        Rows   Bytes    TempSpc         Cost    (%CPU)

 0      SELECT STATEMENT                 2000K   3906K                   104K     (4)
 1      SORT GROUP BY                    2000K   3906K     30M           104K     (4)       
 2      TABLE ACCESS FULL     EMP        2000K   3906K                   99312    (4)