2011-11-29 11G新功能：PL/SCOPE

http://www.itpub.net/thread-1499223-20-1.html

197樓

我在當前會話把PL/Scope打開：

ALTER SESSION SET plscope_settings='identifiers:all'
/

然后我創建了這個包頭：

CREATE OR REPLACE PACKAGE plch_pkg
IS
   PROCEDURE do_stuff;
END plch_pkg;
/

下列哪些查詢實現了一個包體，從而使得下列的查詢：

SELECT name, usage
  FROM user_identifiers
WHERE     object_name = 'PLCH_PKG'
       AND type IN ('PROCEDURE', 'FUNCTION')
ORDER BY usage
/

會輸出這些結果：

NAME       USAGE      
---------- -----------
DO_STUFF   CALL      
DO_STUFF   DECLARATION
DO_STUFF   DECLARATION
DO_STUFF   DEFINITION
DO_STUFF   DEFINITION

(A)

CREATE OR REPLACE PACKAGE BODY plch_pkg
IS
   PROCEDURE do_stuff (number_in IN NUMBER)
   IS
   BEGIN
      NULL;
   END do_stuff;
   PROCEDURE do_stuff
   IS
   BEGIN
      NULL;
   END do_stuff;
END plch_pkg;
/

SQL> SELECT name, usage
  2    FROM user_identifiers
  3  WHERE     object_name = 'PLCH_PKG'
  4         AND type IN ('PROCEDURE', 'FUNCTION')
  5  ORDER BY usage
  6  /
NAME                                                                             USAGE
-------------------------------------------------------------------------------- -----------
DO_STUFF                                                                         DECLARATION
DO_STUFF                                                                         DECLARATION
DO_STUFF                                                                         DEFINITION
DO_STUFF                                                                         DEFINITION
SQL>

(B)

CREATE OR REPLACE PACKAGE BODY plch_pkg
IS
   PROCEDURE do_stuff
   IS
   BEGIN
      NULL;
   END do_stuff;
END plch_pkg;
/

SQL> 
SQL> SELECT name, usage
  2    FROM user_identifiers
  3  WHERE     object_name = 'PLCH_PKG'
  4         AND type IN ('PROCEDURE', 'FUNCTION')
  5  ORDER BY usage
  6  /
NAME                                                                             USAGE
-------------------------------------------------------------------------------- -----------
DO_STUFF                                                                         DECLARATION
DO_STUFF                                                                         DEFINITION
SQL>

(C)

CREATE OR REPLACE PACKAGE BODY plch_pkg
IS
   PROCEDURE do_stuff (number_in IN NUMBER)
   IS
   BEGIN
      NULL;
   END do_stuff;
   PROCEDURE do_stuff
   IS
   BEGIN
      do_stuff (1);
   END do_stuff;
END plch_pkg;
/

SQL> SELECT name, usage
  2    FROM user_identifiers
  3  WHERE     object_name = 'PLCH_PKG'
  4         AND type IN ('PROCEDURE', 'FUNCTION')
  5  ORDER BY usage
  6  /
NAME                                                                             USAGE
-------------------------------------------------------------------------------- -----------
DO_STUFF                                                                         CALL
DO_STUFF                                                                         DECLARATION
DO_STUFF                                                                         DECLARATION
DO_STUFF                                                                         DEFINITION
DO_STUFF                                                                         DEFINITION
SQL>

(D)

CREATE OR REPLACE PACKAGE BODY plch_pkg
IS
   PROCEDURE do_stuff (number_in IN NUMBER)
   IS
   BEGIN
      NULL;
   END do_stuff;
   PROCEDURE do_stuff
   IS
   BEGIN
      NULL;
   END do_stuff;
BEGIN
   do_stuff (1);
END plch_pkg;
/

SQL> SELECT name, usage
  2    FROM user_identifiers
  3  WHERE     object_name = 'PLCH_PKG'
  4         AND type IN ('PROCEDURE', 'FUNCTION')
  5  ORDER BY usage
  6  /
NAME                                                                             USAGE
-------------------------------------------------------------------------------- -----------
DO_STUFF                                                                         CALL
DO_STUFF                                                                         DECLARATION
DO_STUFF                                                                         DECLARATION
DO_STUFF                                                                         DEFINITION
DO_STUFF                                                                         DEFINITION
SQL>

答案說明在202樓

2011-11-29 答案CD

A:在此選項中do_stuff被重載，所以DECLARATION 和 DEFINITION的顯示行數是正確的。但是，并沒有對do_stuff的調用。

B:為了使得DECLARATION 和 DEFINITION各顯示兩行，do_stuff必須被重載。

C:既有重載又有調用，正確。

D:同上，只是調用的地方不同。