声明的数据类型：无效的标识符

Question

drop type name_Domain force;

CREATE OR REPLACE TYPE name_Domain AS OBJECT(
  FirstName VARCHAR2(30), 
  LastName varchar2(15)
);

---

   drop table Race;

   CREATE TABLE Race
   (
      RaceID ID_Domain, 
      Location name_Domain, 
   );

---

// new sql

ALTER TABLE Racecourse ADD CONSTRAINT pk_racecourse PRIMARY KEY (Name);

----＆gt;错误报告：

   SQL Error: ORA-00904: "NAME": invalid identifier
   00904. 00000 -  "%s: invalid identifier"

我正在尝试在新的sql文件中设置约束，但是ORACLE SQL开发人员向我抛出了这个错误?????????