object - 从子类型初始化对象

Question

我需要使用 PL/SQL 中的超类型 A 从子类型 B 创建和初始化对象：

create or replace 
TYPE "A" as object{
school_category  varchar(10);
}

create or replace 
TYPE "B" UNDER A {
school_name varchar(10);
school_ranking INTEGER;
}

现在，当我运行以下代码时：

Declare 
   i_B B;
BEGIN
  i_B := B('name_sample', 12, A('elementary'));
END;

我得到以下错误：

PLS-00306: wrong number or types of arguments in call to 'B'

我真的很感谢你在这方面的帮助。非常感谢。

Answer 1

试试这个代码： -

 Create Or Replace Type Atest As Object
    (
    School_Category  Varchar2(10)
    );

    create or replace Type Btest Under Atest (
    school_name varchar2(10),
    School_Ranking number
         );

DECLARE
  var2 Btest;
BEGIN
  var2 := Btest('Good','MySchool',2);

    Dbms_Output.Put_Line(var2. School_Category);
    Dbms_Output.Put_Line(var2. school_name);
    Dbms_Output.Put_Line(var2. School_Ranking);
End;

或者

Create Or Replace Type Atest As Object
(
School_Category  Varchar2(10)
);

create or replace Type Btest as Object  (
school_name varchar2(10),
School_Ranking number,
School_Categ  Atest
);

Declare
iobj Btest;
Begin
iobj:=Btest(school_name=>'MYSCHOOL',School_Ranking=>2,School_Categ=>Atest(School_Category=>'GOOD'));

Dbms_Output.Put_Line(Iobj.School_Name);
Dbms_Output.Put_Line(Iobj.School_Ranking);

end;