declare  
temp_emp test_tw%rowtype;   
cursor cur2 is select * from test_tw;   
begin  
if cur2%isopen = false then  
open cur2;   
end if;   
for i in 0..5 loop   
fetch cur2 into temp_emp;   
exit when cur2%notfound;   
dbms_output.put_line('编号：'||temp_emp.id||','||'名字:'||temp_emp.xm);
end loop;   
close cur2;   
end;  

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