oracle - pl/sql 对象类型 "ORA-06530: Reference to uninitialized composite"错误

Question

我有一个类型如下:

CREATE OR REPLACE TYPE tbusiness_inter_item_bag AS OBJECT (
   item_id              NUMBER,
   system_event_cd      VARCHAR2 (20),
   CONSTRUCTOR FUNCTION tbusiness_inter_item_bag RETURN SELF AS RESULT
);
CREATE OR REPLACE TYPE BODY tbusiness_inter_item_bag
AS
   CONSTRUCTOR FUNCTION tbusiness_inter_item_bag RETURN SELF AS RESULT
   AS
   BEGIN
      RETURN;
   END;
END;

当我执行以下脚本时，出现“引用未初始化的复合”错误，恕我直言非常合适。

DECLARE
   item   tbusiness_inter_item_bag;
BEGIN
   item.system_event_cd := 'ABC';
END;

这也引发了同样的错误:

item.item_id := 3;

但是，如果我将对象类型更改为:

CREATE OR REPLACE TYPE tbusiness_inter_item_bag AS OBJECT (
   item_id              NUMBER(1),
   system_event_cd      VARCHAR2 (20),
   CONSTRUCTOR FUNCTION tbusiness_inter_item_bag RETURN SELF AS RESULT
);

然后最后一条语句不再引发错误(我的“项目”仍未初始化):

item.item_id := 3;

我不应该得到相同的 ORA-06530 错误吗？

ps:Oracle 数据库 10g 企业版 10.2.0.4.0 版 - 64bi

Answer 1

我在 Oracle 11gR1 中重现了相同的行为。我同意你的看法，这对我来说也是一个错误，尽管是一个微不足道的错误。

SQL> CREATE OR REPLACE TYPE tbusiness_inter_item_bag AS OBJECT (
  2     item_id              NUMBER(1),
  3     system_event_cd      VARCHAR2 (20),
  4     CONSTRUCTOR FUNCTION tbusiness_inter_item_bag RETURN SELF AS RESULT
  5  );
  6  /

Type created.

SQL> DECLARE
  2     item   tbusiness_inter_item_bag;
  3  BEGIN
  4     item.item_id := 1;
  5  END;
  6  /

PL/SQL procedure successfully completed.

SQL>

请注意，这仍然失败:

SQL> DECLARE
  2     item   tbusiness_inter_item_bag;
  3  BEGIN
  4     item.item_id := 1;
  5     item.system_event_cd := 'ABC';
  6  END;
  7  /
DECLARE
*
ERROR at line 1:
ORA-06530: Reference to uninitialized composite
ORA-06512: at line 5

SQL>

显然，正确的做法是在引用对象之前初始化对象。

SQL> DECLARE
  2     item   tbusiness_inter_item_bag := tbusiness_inter_item_bag();
  3  BEGIN
  4     item.system_event_cd  := 'ABC';
  5  END;
  6  /

PL/SQL procedure successfully completed.

SQL>