oracle 游标例子不同的 打开方式 -判断最后一条记录

--1 显示游标

declare

cursor v_sc1 is

select sendnum,registedate from user_info t for update of t.userlevel,nicheng nowait; --of 后面可以多个变量

n_level number;

n_sendnum number;

d_registedate date;

begin

n_level:=0;

open v_sc1;

loop

fetch v_sc1 into n_sendnum, d_registedate,n_id;

exit when v_sc1%notfound; --一定要有

if (n_sendnum>0) and (n_sendnum<=100) and (d_registedate<add_months(sysdate,-3))then

n_level :=1;

else

n_level :=3;

end if;

update user_info set userlevel = n_level where current of v_sc1; --更新数据 只更新当前数据；不用再次执行全表扫描

end loop;

end;

/

--2 带参数的游标

declare

cursor c_test(pid_1 number,pid_2 number) is select * from t1 where t1.emp_no> pid_1 and t1.emp_no<pid_2 for update of emp_no;

i number:=0;

begin

for i in 100..102 loop --外循环 ：在查询数据量大的表时一次性查出风险太大。可以分批执行

for v_test in c_test(i,i+100) loop

update t1 set t1.tel='13838100400' where current of c_test;

end loop;

commit;

end loop;

end;

--3 另一种打开方式

declare

type refcursor is ref cursor;

v_cursor refcursor;



begin

open cur for select t1.tel from t1;

loop

exit when cur%notfound;

fetch cur into v_tel ;

end loop;

end;

4- 判断游标指向最后一条记录

loop

i:=i+1;

if i=t_cursor%rowcount-1 then

最后一条记录

end if;