java经典 create procedure modify_sc as begin declare cur_sc cursor for select sno,cno,grade from sc; /*检出所有课程的学生成绩取到游标中;*/ declare @ssno char(10),@ccno char(10),@ggrade float; declare @class char(10); open cur_sc; fetch next from cur_sc into @ssno,@ccno,@ggra