SQL語句如下： SELECT 學號, Count(課程編號) AS 課程總數, Sum(成績) AS 總分數, Avg(成績) AS 平均分 FROM 成績表 GROUP BY 學號;SQL常用操作語句如下：選擇：select * from table1 where 範圍 插入：insert into table1(field1,field2) values(value1,value2) 刪除：delete from table1 where 範圍 更新：update table1 set field1=value1 where 範圍 查詢：select * from table1 where field1 like ’%value1%’ 排序：select * from table1 order by field1,field2 [desc] 總數：select count as totalcount from table1 求和：select sum(field1) as sumvalue from table1 平均：select avg(field1) as avgvalue from table1 最大：select max(field1) as maxvalue from table1 最小：select min(field1) as minvalue from table1