PL/SQL SQL CODING GUIDELINE 33 - Always close locally opened cursors

條款三十三，總是關閉開啟的游標。

像是下面這樣將游標開啟後並未揪游標關閉，使用的資源不會自動釋放。

CREATE PROCEDURE not_close_cursor (out_count OUT INTEGER)
AS
CURSOR c1
IS
SELECT COUNT (*)
FROM all_users;
BEGIN
out_count := 0;
OPEN c1;
FETCH c1
INTO out_count;
END not_close_cursor;
...

應該要自己將游標在適當的時機點關閉，使用的資源才會被釋放。

CREATE PROCEDURE close_cursor (out_count OUT INTEGER)
AS
CURSOR c1
IS
SELECT COUNT (*)
FROM all_users;
BEGIN
out_count := 0;
OPEN c1;
FETCH c1
INTO out_count;
CLOSE c1
END close_cursor;