我是 Oracle 对象的新手,我遇到了问题。我不知道如何从 REF 的 VARRAY 中取消引用项目。下面是一些重现我遇到的问题的源代码。错误是:PLS-00306:调用“DEREF”时参数的数量或类型错误
DROP TYPE LOC FORCE
/
DROP TYPE LIST_LOC FORCE
/
DROP TYPE PIZ FORCE
/
CREATE OR REPLACE TYPE LOC AS OBJECT(
NAME VARCHAR2(30),
MEMBER FUNCTION GET_NAME RETURN VARCHAR2
)
/
CREATE OR REPLACE TYPE BODY LOC AS
MEMBER FUNCTION GET_NAME RETURN VARCHAR2 IS
BEGIN
RETURN SELF.NAME;
END;
END;
/
CREATE OR REPLACE TYPE LIST_LOC AS VARRAY(10) OF REF LOC
/
CREATE OR REPLACE TYPE PIZ AS OBJECT(
LOCS LIST_LOC,
MEMBER PROCEDURE DISPLAY_LOCS
)
/
CREATE OR REPLACE TYPE BODY PIZ AS
MEMBER PROCEDURE DISPLAY_LOCS IS
BEGIN
FOR IDX IN SELF.LOCS.FIRST..SELF.LOCS.LAST LOOP
DBMS_OUTPUT.PUT_LINE(DEREF(SELF.LOCS(IDX)).GET_NAME()); --this is the line that generates the error
END LOOP;
END;
END;
/
错误出现在 DISPLAY_LOCS 过程中,当我尝试从 LOCS varray 获取位置 IDX 处的 REF 并对其进行 DEREF 以获取名称时。