同时与groupy count 使用的用法
SQL> select Coder 2 , count(distinct course) 3 , count(*) 4 from offerings 5 group by Coder;
CODER COUNT(DISTINCTCOURSE) COUNT(*) ---------- --------------------- ---------- 1 2 3 4 2 2 8 2 2 11 1 1 13 2 2 3 3
6 rows selected.