ORA-00904 :標識符無效

• 執行如下SQL 出現以下ERROR

create or replace procedure P_DISTABLE_FK(IN_TABLE in varchar2) is
--失效 輸入表名稱的外鍵
V_SQL VARCHAR2(200) ;
V_FK  VARCHAR2(60); 
begin
      --查詢外鍵名稱
      V_SQL :='SELECT * FROM USER_CONSTRAINTS WHERE CONSTRAINT_TYPE='|| 'R'||  '  and  table_name='||IN_TABLE;
       dbms_output.put_line(  ' V_SQL IS ' ||  V_SQL);
    
      execute immediate V_SQL into V_FK;
      v_sql:='alter table'|| IN_TABLE ||'disable constraint '||V_FK;  
      EXECUTE IMMEDIATE v_sql;
end P_DISTABLE_FK;

• 打印 V_SQL 變量　：

 V_SQL IS SELECT * FROM USER_CONSTRAINTS WHERE CONSTRAINT_TYPE=R  and  table_name='B';

• 發現問題出在：CONSTRAINT_TYPE=R

 SQL 應該為：SELECT * FROM USER_CONSTRAINTS WHERE CONSTRAINT_TYPE='R'  and  table_name='B';

修改存儲過程：

create or replace procedure P_DISTABLE_FK(IN_TABLE in varchar2,IN_TYPE IN VARCHAR2) is
--失效 輸入表名稱的外鍵
V_SQL VARCHAR2(200) ;
V_FK  VARCHAR2(60);  
begin
      --查詢外鍵名稱
      V_SQL :='SELECT * FROM USER_CONSTRAINTS WHERE CONSTRAINT_TYPE='|| IN_TYPE||  '  and  table_name='||IN_TABLE;
       dbms_output.put_line(  ' V_SQL IS ' ||  V_SQL);
    
      execute immediate V_SQL into V_FK;
      v_sql:='alter table'|| IN_TABLE ||'disable constraint '||V_FK;  
      EXECUTE IMMEDIATE v_sql;
end P_DISTABLE_FK;

這樣輸出的SQL 就為：正確形式了

SELECT * FROM USER_CONSTRAINTS WHERE CONSTRAINT_TYPE='R'  and  table_name='B'