oracle 统计成绩
set serveroutput on; declare cursor c1 is select dno,dname from dep; pdno dep.dno%TYPE; pdname dep.dname%type; cursor c2(aa varchar2,bb number) is select grade from sc where cno=(select cno from course where cname=aa) and sno in (select sno from student where dno=bb); pgrade sc.grade%type; count1 number;count2 number;count3 number;avgg number; coursename varchar2(100):='大学物理'; begin open c1; loop fetch c1 into pdno,pdname; exit when c1%notfound; count1 :=0;count2 :=0;count3 :=0; select avg(grade) into avgg from sc where cno=(select cno from course where cname=coursename) and sno in (select sno from student where dno=pdno); open c2(coursename,pdno); loop fetch c2 into pgrade; exit when c2%notfound; if pgrade <60 then count1:=count1+1; elsif pgrade >60 and pgrade <=80 then count2:=count2+1; else count3:=count3+1; end if; end loop; close c2; insert into msg values (coursename,pdname,count1,count2,count3,avgg); end loop; close c1; dbms_output.put_line('统计完成'); end; /
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