请说出该程序段的功能。
declare @e numeric(5,2)
declare @ c1 int, @ c2 int, @ c3 int, @ c4 int
set @ c1=0; set @ c2 =0; set @ c3=0; set @ c4=0
declare xxx cursor
for select 成绩 from score
open xxx
fetch xxx into @ c
while @'@ fetch_status = 0
begin
if(@c ＞ =90) set @cl =@ e1 +1;
else if( @ c ＞ =70) set @ c2 =@ c2 +1;
else if(@ c＞ =60) set @ c3 =@ c3 +1;
else set @ c4 = @ c4 + 1
fetch from xxx into @ c
end
close xxx
deallocate xxx
print 优秀生人数：'+sb(@ c1，5)；
print食好生人数：'+str(@ c2，5)；
print及格生人数：'+str(@ c3，5)；
print及格生人数：'+sh(@ c4，5)
