oralce循環(huán)問題，求助

counter1219

declare
cursor c1 is select view_name from all_views where rownum <=10 order by view_name;
vname varchar2(40);
begin
open c1;
fetch c1 into vname;
while c1%FOUND LOOP
DBMS_OUTPUT.put_LINE(vname);
END LOOP;
CLOSE c1;
END;

為什么查詢出來的結(jié)果，進入死循環(huán)了呢，結(jié)果如下：

JAVASNM
JAVASNM
JAVASNM
JAVASNM
JAVASNM
JAVASNM
JAVASNM
.............


查詢出來的結(jié)果應(yīng)該是下面的結(jié)果的，
SQL> select view_name from all_views where rownum <=10 order by view_name;

VIEW_NAME
------------------------------
JAVASNM
KU$_10_1_AUDIT_VIEW
KU$_10_1_COMMENT_VIEW
KU$_10_1_DBLINK_VIEW
KU$_10_1_FHTABLE_VIEW
KU$_10_1_HISTGRM_MAX_VIEW
KU$_10_1_HISTGRM_MIN_VIEW
KU$_10_1_HTABLE_VIEW
KU$_10_1_IND_STATS_VIEW
KU$_10_1_IOTABLE_VIEW

10 rows selected

SQL>

asdf2110

循環(huán)內(nèi)要不斷 fetch 才行

回復(fù) 1# counter1219


   

counter1219

麻煩解釋下需要怎么修改，不是先獲�。╢etch）再循環(huán)的么？回復(fù) 2# asdf2110


   

asdf2110

fetch 每次只能fetch一條啊
如果想獲取第二、第三，。。。就要不斷的調(diào)用 fetch

回復(fù) 3# counter1219


   

counter1219

create or replace procedure qqpro
as
cursor c1 is select id from qq where rownum <=4 order by id;
vname varchar2(40);
begin
open c1;
LOOP
exit when c1%NOTFOUND;
fetch c1 into vname;
DBMS_OUTPUT.put_LINE(vname);
END LOOP;
CLOSE c1;
END;

SQL> exec qqpro;

PL/SQL procedure successfully completed

SQL> set serveroutput on;
SQL> exec qqpro;

1
2
3
4
4       --------   為什么最后一行會打印兩次？PL/SQL procedure successfully completed

SQL>  select id from qq where rownum <=4 order by id;

   ID
-----
    1
    2
    3
    4

SQL>

counter1219

create or replace procedure qqpro
as
cursor c1 is select id from qq where rownum <=4 order by id;
vname varchar2(40);
begin
open c1;
LOOP
fetch c1 into vname;
exit when c1%NOTFOUND;DBMS_OUTPUT.put_LINE(vname);  對換位置后，執(zhí)行結(jié)果是正確的了，這個是什么原因？
END LOOP;
CLOSE c1;
END;

doni

循環(huán)邏輯問題，先做邏輯判斷，還是先輸出，當(dāng)然結(jié)果就不一樣了