oracle - 试图从 Oracle 函数中获取表。改为获取不一致的数据类型

Question

我正在尝试从 Oracle 中的存储函数返回查询。这个简单的尝试失败了：

CREATE OR REPLACE TYPE GetObjectsForFolderObjectType IS OBJECT (
       FOLDER_ID NUMBER(9), OBJECT_ID NUMBER(9)
);

CREATE OR REPLACE TYPE GetObjectsForFolderTableType IS
       TABLE OF GetObjectsForFolderObjectType;

CREATE OR REPLACE FUNCTION GetObjectsForFolder
       (FOLDER_ID INTEGER, FOLDER_DATA_TABLE VARCHAR2)
RETURN GetObjectsForFolderTableType IS 
       THE_RESULT GetObjectsForFolderTableType := GetObjectsForFolderTableType ( );
BEGIN 
       EXECUTE IMMEDIATE 'SELECT * FROM '||FOLDER_DATA_TABLE BULK COLLECT INTO THE_RESULT;
       RETURN THE_RESULT;
END; 

SELECT * FROM TABLE(GetObjectsForFolder(1, 'MY_TABLE_NAME'));

上面的结果是

ORA-00932: inconsistent datatypes: expected - got -
ORA-06512: at "USERNAME.GETOBJECTSFORFOLDER", line 6
00932. 00000 -  "inconsistent datatypes: expected %s got %s"
*Cause:    
*Action:

注意：虽然我在示例中掩盖了一些内容，但 ORA-00932 行确实显示“预期 - 得到 -”。

Answer 1

在您的动态 PL/SQL 语句中，您不能将表列直接批量收集到您的对象表中。相反，您必须先将列选择到对象中，然后将对象批量收集到表类型中：

    CREATE OR REPLACE TYPE GetObjectsForFolderObjectType IS OBJECT (
           FOLDER_ID NUMBER(9), OBJECT_ID NUMBER(9)
    );

    CREATE OR REPLACE TYPE GetObjectsForFolderTableType IS
           TABLE OF GetObjectsForFolderObjectType;

    CREATE OR REPLACE FUNCTION GetObjectsForFolder
           (FOLDER_ID INTEGER, FOLDER_DATA_TABLE VARCHAR2)
    RETURN GetObjectsForFolderTableType IS 
           THE_RESULT GetObjectsForFolderTableType := GetObjectsForFolderTableType ( );
    BEGIN 
           EXECUTE IMMEDIATE 'SELECT GetObjectsForFolderObjectType(folder_id, object_id) FROM '||FOLDER_DATA_TABLE BULK COLLECT INTO THE_RESULT;
           RETURN THE_RESULT;
    END;