具有未知陈旧性的物化视图 - Oracle 11G

Materialized View having UNKNOWN staleness - Oracle 11G

我正在使用 Oracle 11G。
我的实体化视图之一已变为未知 (MY_MAT_VW1)。您可以在下面查看 ALL_MVIEWS 的输出。

OWNER | MVIEW_NAME | CONTAINER_NAME | QUERY    | QUERY_LEN   | UPDATABLE | UPDATE_LOG | MASTER_ROLLBACK_SEG | MASTER_LINK | REWRITE_ENABLED | REWRITE_CAPABILITY | REFRESH_MODE     | REFRESH_METHOD     | BUILD_MODE   | FAST_REFRESHABLE | LAST_REFRESH_TYPE  | LAST_REFRESH_DATE | STALENESS       |  AFTER_FAST_REFRESH | UNKNOWN_PREBUILT  | UNKNOWN_PLSQL_FUNC   | UNKNOWN_EXTERNAL_TABLE  |  UNKNOWN_CONSIDER_FRESH | UNKNOWN_IMPORT | UNKNOWN_TRUSTED_FD   | COMPILE_STATE  | USE_NO_INDEX  | STALE_SINCE | NUM_PCT_TABLES | NUM_FRESH_PCT_REGIONS | NUM_STALE_PCT_REGIONS
-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
MY_DB | MY_MAT_VW1 | MY_MAT_VW1     | select.. | 6728        | N         |            |                     |             | N               | GENERAL            | DEMAND           | COMPLETE           | IMMEDIATE    | NO               | COMPLETE           | 14-Nov-16         | UNKNOWN         |  NA                 | N                 | Y                    | N                       |  N                      | N              | N                    | VALID          | N             | 0           |                |                       | 
MY_DB | MY_MAT_VW2 | MY_MAT_VW2     | select.. | 7074        | N         |            |                     |             | N               | TEXTMATCH          | DEMAND           | COMPLETE           | IMMEDIATE    | NO               | COMPLETE           | 13-Nov-16         | FRESH           |  NA                 | N                 | N                    | N                       |  N                      | N              | N                    | FRESH          | N             | 0           | 0              |                       | 

实体化视图的查询包含多个表、内联视图和联合之间的复杂连接。
根据我的理解(UNKNOWN_PLSQL_FUNC 列),我猜有一个 PLSQL 函数导致陈旧变得未知。但是我不确定是哪一个。
我尝试重新编译并刷新它,但没有成功。
任何人都可以向我提供一些有关如何检测根本原因并确保它不会再次变为 UNKNOWN 的信息。
它对其中存储的数据有什么影响吗?
下面只是我为复制该场景而创建的示例。

SELECT * FROM ENTITY_T;

ID | ENTITY_TYPE | FIRST_NAME | LAST_NAME |  LEGAL_NAME
--------------------------------------------------
1  | INDIVIDUAL  | JOHN       | LESSEN    |
2  | INDIVIDUAL  | ROSAN      | MEL       |
3  | CORP        | SIGMA      |           | SIGMA CORPORATION


--Function to get name base upon type
CREATE OR REPLACE FUNCTION GET_NAME (P_ID IN NUMBER)
RETURN VARCHAR2
DETERMINISTIC
AS
LV_NAME VARCHAR2(200);
BEGIN
SELECT CASE ENTITY_TYPE WHEN 'INDIVIDUAL' THEN FIRST_NAME ||' '|| LAST_NAME
                        WHEN 'CORP' THEN LEGAL_NAME
                        ELSE 'NONE'
        END INTO LV_NAME
FROM ENTITY_T
WHERE ID=P_ID;
RETURN LV_NAME;
EXCEPTION
WHEN NO_DATA_FOUND THEN
   RETURN 'NO ID FOUND';
WHEN OTHERS THEN
   RETURN 'OTHER ERROR';
END;

--Materialized view creation 
CREATE MATERIALIZED VIEW TEST_MV
AS
SELECT ID,ENTITY_TYPE,GET_NAME(ID) NAME
FROM ENTITY_T;


SELECT MVIEW_NAME,STALENESS,AFTER_FAST_REFRESH,UNKNOWN_PLSQL_FUNC,COMPILE_STATE,STALE_SINCE 
FROM ALL_MVIEWS WHERE MVIEW_NAME='TEST_MV';

MVIEW_NAME | STALENESS | AFTER_FAST_REFRESH | UNKNOWN_PLSQL_FUNC | COMPILE_STATE | STALE_SINCE
----------------------------------------------------------------------------------------------
TEST_MV    | UNKNOWN   | NA                 | Y                  | VALID         |  

根据 My Oracle Support,这可能是一个错误 (7582462)。

由于没有解决此错误的方法,您必须处理陈旧性将显示 unknown 的事实,或者不在实体化视图定义上使用函数。

参考:DBA_MVIEWS Shows STALENESS Value of UNKNOWN After Refresh (Doc ID 757537.1)

JSapkota 提到的 Oracle Issue/Doc ID 757537.1 明确指出,这不是错误,而是 correct/expected 行为:

STALENESS of the mview, refering to PL/SQL function is set to UNKOWN as one cannot determine PL/SQL function changes. Current behaviour is correct as per the design & code.

我想使用 DETERMINISTIC 函数而不是默认范围可以防止它。