如何从BasicFile迁移到SecureFile存储

　Oracle 11g新的SecureFile存储特性扩展了大对象(LOB)的灵活性和容量，本文研究如何有效地从BasicFile迁移到SecureFile存储，如何测量SecureFile vs BasicFile LOB的效率，以及如何为SecureFile LOB使用不同的压缩和重复数据删除选项。

　　我创建了一个新表TRBTKT.SECURE_TICKETS重新定义了原始表TRBTKT.TICKETS的结构，将原始的BasicFile LOB映射到对应的SecureFile LOB，然后执行了一条INSERT INTO … SELECT FROM DML语句将原始表中的内容传输到新表中。

　　在一个相对简单的应用程序环境中，这种载入方式足以应付，但目前在数据仓库和商业智能应用程序中广泛地使用了LOB，特别是存储那些包含了复杂商务交易的XML文档和医院信息系统捕获到的医疗影像数据。

　　为了便于说明，我使用清单1中的代码重新创建了这两个表，我使用了列表分区对这两个表进行了分区，在清单2中，我使用更大的数据重新载入TRBTKT.TICKETS表。

　　清单1 使用列表分区重新创建这两个表以模拟数据仓库环境

--  重新创建表TRBTKT.TICKETS，这次包括了一个STATUS列
CREATE   TABLE  trbtkt.tickets (
     tkt_id          NUMBER
    ,description     VARCHAR2 ( 30 )
    ,submit_dtm      TIMESTAMP
    ,status          VARCHAR2 ( 8 )
    ,document       BLOB
    ,scrnimg        BLOB
)
    LOB(document)   
        STORE  AS  BASICFILE (TABLESPACE basicfiles)
   ,LOB(scrnimg)    
        STORE  AS  BASICFILE (TABLESPACE basicfiles)
    PARTITION  BY  LIST (status) (
        PARTITION sts_open 
             VALUES  ( ' OPEN ' )
       ,PARTITION sts_pending
             VALUES  ( ' PENDING ' )
       ,PARTITION sts_closed
             VALUES  ( ' CLOSED ' )
       ,PARTITION sts_other
             VALUES  ( DEFAULT )
    )
;

-- 注释
COMMENT  ON   TABLE  trbtkt.tickets
     IS   ' Contains Trouble Ticket transaction data ' ;
COMMENT  ON   COLUMN  trbtkt.tickets.tkt_id
     IS   ' Unique identifier for a Trouble Ticket ' ;
COMMENT  ON   COLUMN  trbtkt.tickets.description
     IS   ' Trouble Ticket Description ' ;
COMMENT  ON   COLUMN  trbtkt.tickets.submit_dtm
     IS   ' Trouble Ticket Submission Time Stamp ' ;
COMMENT  ON   COLUMN  trbtkt.tickets.status
     IS   ' Trouble Ticket Status ' ;
COMMENT  ON   COLUMN  trbtkt.tickets.document
     IS   ' Large Object (LOB) that contains a Microsoft Word document that provides detailed information about a Trouble Ticket ' ;
COMMENT  ON   COLUMN  trbtkt.tickets.scrnimg
     IS   ' Large Object (LOB) that contains a screen print or other image that helps a problem solver identify how to act on a Trouble Ticket ' ;

--  创建索引和约束
CREATE   UNIQUE   INDEX  trbtkt.tickets_pk_idx
     ON  trbtkt.tickets(tkt_id)
    TABLESPACE users;

ALTER   TABLE  trbtkt.tickets
     ADD   CONSTRAINT  tickets_pk
     PRIMARY   KEY  (tkt_id);

-- ---
--  创建表TRBTKT.SECURE_TICKETS的一个改良版本，使用分区划分SecureFile LOB的存储，基于STATUS 的值设置合适的保留周期
DROP   TABLE  trbtkt.secure_tickets PURGE;
CREATE   TABLE  trbtkt.secure_tickets (
     tkt_id          NUMBER
    ,description     VARCHAR2 ( 30 )
    ,submit_dtm      TIMESTAMP
    ,status          VARCHAR2 ( 8 )
    ,document       BLOB
    ,scrnimg        BLOB
)
    LOB(document)   
        STORE  AS  SECUREFILE (
            TABLESPACE securefiles
            DISABLE STORAGE  IN  ROW
            CACHE
        )
   ,LOB(scrnimg)    
        STORE  AS  SECUREFILE (
            TABLESPACE securefiles
            DISABLE STORAGE  IN  ROW
            CACHE READS
        )
    PARTITION  BY  LIST (status) (
        PARTITION sts_open 
             VALUES  ( ' OPEN ' )
                LOB (document) STORE  AS  SECUREFILE (KEEP_DUPLICATES NOCOMPRESS)
               ,LOB (scrnimg)  STORE  AS  SECUREFILE (KEEP_DUPLICATES COMPRESS)
       ,PARTITION sts_pending
             VALUES  ( ' PENDING ' )
                LOB (document) STORE  AS  SECUREFILE (KEEP_DUPLICATES NOCOMPRESS)
               ,LOB (scrnimg)  STORE  AS  SECUREFILE (DEDUPLICATE COMPRESS)
       ,PARTITION sts_closed
             VALUES  ( ' CLOSED ' )
                LOB (document) STORE  AS  SECUREFILE (DEDUPLICATE COMPRESS)
               ,LOB (scrnimg)  STORE  AS  SECUREFILE (DEDUPLICATE COMPRESS HIGH)
       ,PARTITION sts_other
             VALUES  ( DEFAULT )
                LOB (document) STORE  AS  SECUREFILE (DEDUPLICATE COMPRESS HIGH)
               ,LOB (scrnimg)  STORE  AS  SECUREFILE (DEDUPLICATE COMPRESS HIGH)
    )
;

-- 注释
COMMENT  ON   TABLE  trbtkt.secure_tickets
     IS   ' Contains Trouble Ticket transaction data ' ;
COMMENT  ON   COLUMN  trbtkt.secure_tickets.tkt_id
     IS   ' Unique identifier for a Trouble Ticket ' ;
COMMENT  ON   COLUMN  trbtkt.secure_tickets.description
     IS   ' Trouble Ticket Description ' ;
COMMENT  ON   COLUMN  trbtkt.secure_tickets.submit_dtm
     IS   ' Trouble Ticket Submission Time Stamp ' ;
COMMENT  ON   COLUMN  trbtkt.secure_tickets.status
     IS   ' Trouble Ticket Status ' ;
COMMENT  ON   COLUMN  trbtkt.secure_tickets.document
     IS   ' Large Object (LOB) that contains a Microsoft Word document that provides detailed information about a Trouble Ticket ' ;
COMMENT  ON   COLUMN  trbtkt.secure_tickets.scrnimg
     IS   ' Large Object (LOB) that contains a screen print or other image that helps a problem solver identify how to act on a Trouble Ticket ' ;

　　　清单2 使用附加数据重新载入表TRBTKT.TICKETS

SET  SERVEROUTPUT  ON
TRUNCATE   TABLE  trbtkt.tickets;

BEGIN

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   101
        ,description  =>   ' Trouble Ticket 101 '
        ,submit_dts  =>   ' 2008-12-31 23:45:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_101.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
    );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   102
        ,description  =>   ' Trouble Ticket 102 '
        ,submit_dts  =>   ' 2009-01-04 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_102.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   103
        ,description  =>   ' Trouble Ticket 103 '
        ,submit_dts  =>   ' 2009-01-02 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_103.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
     );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   104
        ,description  =>   ' Trouble Ticket 104 '
        ,submit_dts  =>   ' 2009-01-14 12:30:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_104.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
   );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   105
        ,description  =>   ' Trouble Ticket 105 '
        ,submit_dts  =>   ' 2009-01-09 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_105.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   106
        ,description  =>   ' Trouble Ticket 106 '
        ,submit_dts  =>   ' 2009-01-11 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_106.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );
    
    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   107
        ,description  =>   ' Trouble Ticket 107 '
        ,submit_dts  =>   ' 2009-01-16 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_107.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
    );
    
    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   108
        ,description  =>   ' Trouble Ticket 108 '
        ,submit_dts  =>   ' 2009-01-12 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_108.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );
    
    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   109
        ,description  =>   ' Trouble Ticket 109 '
        ,submit_dts  =>   ' 2009-01-02 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_109.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
     );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   110
        ,description  =>   ' Trouble Ticket 110 '
        ,submit_dts  =>   ' 2009-01-14 12:45:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_110.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
   );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   201
        ,description  =>   ' Trouble Ticket 201 '
        ,submit_dts  =>   ' 2008-12-31 23:45:00 '
        ,status  =>   ' PENDING '
        ,docFileName  =>   ' New_101.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
    );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   202
        ,description  =>   ' Trouble Ticket 202 '
        ,submit_dts  =>   ' 2009-01-04 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_102.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   203
        ,description  =>   ' Trouble Ticket 203 '
        ,submit_dts  =>   ' 2009-01-02 00:00:00 '
        ,status  =>   ' CLOSED '
        ,docFileName  =>   ' New_103.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
     );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   204
        ,description  =>   ' Trouble Ticket 204 '
        ,submit_dts  =>   ' 2009-01-14 12:30:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_104.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
   );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   205
        ,description  =>   ' Trouble Ticket 205 '
        ,submit_dts  =>   ' 2009-01-09 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_105.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   206
        ,description  =>   ' Trouble Ticket 206 '
        ,submit_dts  =>   ' 2009-01-11 00:00:00 '
        ,status  =>   ' PENDING '
        ,docFileName  =>   ' New_106.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );
    
    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   207
        ,description  =>   ' Trouble Ticket 207 '
        ,submit_dts  =>   ' 2009-01-16 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_107.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
    );
    
    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   208
        ,description  =>   ' Trouble Ticket 208 '
        ,submit_dts  =>   ' 2009-01-12 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_108.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );
    
    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   209
        ,description  =>   ' Trouble Ticket 209 '
        ,submit_dts  =>   ' 2009-01-02 00:00:00 '
        ,status  =>   ' PENDING '
        ,docFileName  =>   ' New_109.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
     );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   210
        ,description  =>   ' Trouble Ticket 210 '
        ,submit_dts  =>   ' 2009-01-14 12:45:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_110.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
   );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   301
        ,description  =>   ' Trouble Ticket 301 '
        ,submit_dts  =>   ' 2008-12-31 23:45:00 '
        ,status  =>   ' CLOSED '
        ,docFileName  =>   ' New_101.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
    );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   302
        ,description  =>   ' Trouble Ticket 302 '
        ,submit_dts  =>   ' 2009-01-04 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_102.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   303
        ,description  =>   ' Trouble Ticket 303 '
        ,submit_dts  =>   ' 2009-01-02 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_103.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
     );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   304
        ,description  =>   ' Trouble Ticket 304 '
        ,submit_dts  =>   ' 2009-01-14 12:30:00 '
        ,status  =>   ' CLOSED '
        ,docFileName  =>   ' New_104.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
   );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   305
        ,description  =>   ' Trouble Ticket 305 '
        ,submit_dts  =>   ' 2009-01-09 00:00:00 '
        ,status  =>   ' PENDING '
        ,docFileName  =>   ' New_105.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   306
        ,description  =>   ' Trouble Ticket 306 '
        ,submit_dts  =>   ' 2009-01-11 00:00:00 '
        ,status  =>   ' CLOSED '
        ,docFileName  =>   ' New_106.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );
    
    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   307
        ,description  =>   ' Trouble Ticket 307 '
        ,submit_dts  =>   ' 2009-01-16 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_107.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
    );
    
    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   308
        ,description  =>   ' Trouble Ticket 308 '
        ,submit_dts  =>   ' 2009-01-12 00:00:00 '
        ,status  =>   ' OPEN '
        ,docFileName  =>   ' New_108.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
    );
    
    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   309
        ,description  =>   ' Trouble Ticket 309 '
        ,submit_dts  =>   ' 2009-01-02 00:00:00 '
        ,status  =>   ' CLOSED '
        ,docFileName  =>   ' New_109.doc '
        ,imgFileName  =>   ' Unresolved.jpg '
     );

    trbtkt.pkg_securefiles.AddTroubleTicket (
         tkt_id  =>   310
        ,description  =>   ' Trouble Ticket 310 '
        ,submit_dts  =>   ' 2009-01-14 12:45:00 '
        ,status  =>   ' CLOSED '
        ,docFileName  =>   ' New_110.doc '
        ,imgFileName  =>   ' DBRIssues.jpg '
   );

     COMMIT ;
   
END ;
/
--  收集优化器统计信息
BEGIN
    DBMS_STATS.GATHER_SCHEMA_STATS(ownname  =>   ' TRBTKT ' ,  CASCADE   =>  TRUE);
END ;

/

有效地从BasicFile移植到SecureFile

　　现在已经将这些表进行了分区，以便在数据仓库环境更有效地使用，我也已经考虑过如何将LOB从BasicFile格式快速有效地转换成对应的SecureFile格式，幸运的是，Oracle 11g提供了两个方法：分区交换和在线重定义。

　　1、分区交换

　　分区交换载入(Partition Exchange Load，即PDL)有时也叫做分区转动，包含创建一个非分区表，它的格式和内容完全匹配目标分区表想要的分区，一旦原始表创建好了，就可以开始可已经分区的表的目标分区进行交换了，这个方法确实提供了许多好处，换句话说，原始表的本地索引在交换期间得到维护，它可以并行执行，这个方法可以重复多次以填充每个分区，它的主要缺点是接收数据的分区在进行交换时必须离线。

　　2、在线重定义

　　Oracle推荐使用DBMS_REDEFINITION包对源表和目标表执行在线重定义，因为它实现了分区交换方法相同的目标。但它不需要在重定义过程中将目标离线。在线重定义可以在表级也可以在分区级执行，它也可以同时并行为多个分区执行，我喜欢在线重定义的特性是在这个过程成功执行完毕后，源和目标对象将对真正地在数据库数据目录中转换定义，这意味着任何引用了新对象名的PL/SQL对象都不需要进行任何修改。清单3显示了如何使用TRBTKT.TICKETS表作为源对象，使用TRBTKT.SECURE_TICKETS表作为目标对象进行在线重定义的。从BasicFile LOB转换到SecureFile LOB最后一个注意事项是：一旦转换完成，LOB就不能再降级回到BasicFile LOB了。

　　管理SecureFile元数据

　　这些新的SecureFile特性无疑扩展了LOB的能力，对于DBA而言，也需要注意几个在传统的BasicFile LOB上增加的额外属性，幸运的是，Oracle 11g提供了多个方法跟踪BasicFile和SecureFile LOB的元数据。

　　1、数据字典视图

　　Oracle 11g也更新了多个关于SecureFile信息的数据字典视图，下面列出这些做了变动的视图。 

　　清单4显示了多条SQL*Plus查询，它们使用了这些数据字典视图返回关于SecureFile元数据的信息，报告1显示了从这些查询返回的结果。

　　清单4 查询BasicFile和SecureFile LOB的元数据

SET  PAGESIZE  1000
SET  LINESIZE  140  
--  视图: DBA_SEGMENTS
-- 显示关于BasicFile 和SecureFile 段的元数据
TTITLE  ' LOB Segment Information|(from DBA_SEGMENTS) '
COL segment_name        FORMAT A30      HEADING  ' Segment Name '
COL segment_type        FORMAT A20      HEADING  ' Segment|Type '
COL segment_subtype     FORMAT A20      HEADING  ' Segment|SubType '
COL partition_name      FORMAT A12      HEADING  ' Partition|Name '
COL tablespace_name     FORMAT A12      HEADING  ' Tablespace '
SELECT  
    segment_name
   ,segment_type
   ,segment_subtype
   ,partition_name
   ,tablespace_name
   FROM  dba_segments
WHERE  owner  =   ' TRBTKT '
ORDER   BY  segment_name
;
TTITLE  OFF
--  视图: DBA_LOBS
-- 显示关于BasicFile和SecureFile LOB的元数据
TTITLE  ' BasicFile and SecureFile LOBs Metadata|(from DBA_LOBS) '
COL table_name      FORMAT A14      HEADING  ' Table '
COL segment_name    FORMAT A26      HEADING  ' Segment '
COL column_name     FORMAT A10      HEADING  ' Column '
COL tablespace_name FORMAT A12      HEADING  ' Tablespace '
COL logging         FORMAT A08      HEADING  ' Logging '
COL cache           FORMAT A10      HEADING  ' Cacheing '
COL in_row          FORMAT A07      HEADING  ' Stored|In Row '
COL encrypt         FORMAT A07      HEADING  ' Encryp-|tion '
COL compression     FORMAT A07      HEADING  ' Compre-|ssion '
COL deduplication   FORMAT A08      HEADING  ' DeDupli-|cation '
COL securefile      FORMAT A07      HEADING  ' Secure|File? '
COL partitioned     FORMAT A07      HEADING  ' Parti-|tioned '
SELECT
    table_name
   ,column_name
   ,segment_name
   ,tablespace_name
   ,logging
   ,cache
   ,in_row
   ,encrypt
   ,compression
   ,deduplication
   ,securefile
   ,partitioned
   FROM  dba_lobs
WHERE  owner  =   ' TRBTKT '
ORDER   BY  table_name, column_name
;
TTITLE  OFF
-- 视图: DBA_PART_LOBS
-- 显示BasicFile和SecureFile LOB的默认值
TTITLE  ' BasicFile and SecureFile Partitioned LOB Default Settings|(from DBA_PART_LOBS) '
COL table_name          FORMAT A20      HEADING  ' Table '
COL column_name         FORMAT A12      HEADING  ' Column '
COL def_cache           FORMAT A12      HEADING  ' Cached '
COL def_tablespace_name FORMAT A12      HEADING  ' Tablespace '
COL def_securefile      FORMAT A12      HEADING  ' SecureFile '
COL def_encrypt         FORMAT A12      HEADING  ' Encrypted '
COL def_compress        FORMAT A12      HEADING  ' Compressed '
COL def_deduplicate     FORMAT A12      HEADING  ' DeDuplicated '
SELECT
    table_name
   ,column_name
   ,def_cache
   ,def_tablespace_name
   ,def_securefile
   ,def_compress
   ,def_deduplicate
   ,def_encrypt
   FROM  dba_part_lobs
WHERE  table_owner  =   ' TRBTKT '
ORDER   BY  table_name, column_name
;
TTITLE  OFF
-- 视图: DBA_LOB_PARTITIONS
-- 在独立的LOB级描述BasicFile和SecureFile设置
TTITLE  ' BasicFile and SecureFile LOB Partitions|(from DBA_LOB_PARTITIONS) '
COL table_name      FORMAT A16      HEADING  ' Table '
COL column_name     FORMAT A12      HEADING  ' Column '
COL partition_name  FORMAT A12      HEADING  ' Stored in|Partition '
COL cache           FORMAT A10      HEADING  ' Cacheing '
COL in_row          FORMAT A10      HEADING  ' Stored|In Row '
COL encrypt         FORMAT A10      HEADING  ' Encrypted '
COL compression     FORMAT A10      HEADING  ' Compressed '
COL deduplication   FORMAT A10      HEADING  ' DeDupli-|cated '
COL securefile      FORMAT A10      HEADING  ' SecureFile? '
SELECT
    table_name
   ,column_name
   ,partition_name
   ,cache
   ,in_row
   ,encrypt
   ,compression
   ,deduplication
   ,securefile
   FROM  dba_lob_partitions
WHERE  table_owner  =   ' TRBTKT '
ORDER   BY  table_name, column_name
;
TTITLE  OFF

报告1 从BasicFIle和SecureFile LOB元数据报告返回的结果

SET  PAGESIZE  1000
SET  LINESIZE  140  
--  视图: DBA_SEGMENTS
-- 显示关于BasicFile 和SecureFile 段的元数据
TTITLE  ' LOB Segment Information|(from DBA_SEGMENTS) '
COL segment_name        FORMAT A30      HEADING  ' Segment Name '
COL segment_type        FORMAT A20      HEADING  ' Segment|Type '
COL segment_subtype     FORMAT A20      HEADING  ' Segment|SubType '
COL partition_name      FORMAT A12      HEADING  ' Partition|Name '
COL tablespace_name     FORMAT A12      HEADING  ' Tablespace '
SELECT  
    segment_name
   ,segment_type
   ,segment_subtype
   ,partition_name
   ,tablespace_name
   FROM  dba_segments
WHERE  owner  =   ' TRBTKT '
ORDER   BY  segment_name
;
TTITLE  OFF
--  视图: DBA_LOBS
-- 显示关于BasicFile和SecureFile LOB的元数据
TTITLE  ' BasicFile and SecureFile LOBs Metadata|(from DBA_LOBS) '
COL table_name      FORMAT A14      HEADING  ' Table '
COL segment_name    FORMAT A26      HEADING  ' Segment '
COL column_name     FORMAT A10      HEADING  ' Column '
COL tablespace_name FORMAT A12      HEADING  ' Tablespace '
COL logging         FORMAT A08      HEADING  ' Logging '
COL cache           FORMAT A10      HEADING  ' Cacheing '
COL in_row          FORMAT A07      HEADING  ' Stored|In Row '
COL encrypt         FORMAT A07      HEADING  ' Encryp-|tion '
COL compression     FORMAT A07      HEADING  ' Compre-|ssion '
COL deduplication   FORMAT A08      HEADING  ' DeDupli-|cation '
COL securefile      FORMAT A07      HEADING  ' Secure|File? '
COL partitioned     FORMAT A07      HEADING  ' Parti-|tioned '
SELECT
    table_name
   ,column_name
   ,segment_name
   ,tablespace_name
   ,logging
   ,cache
   ,in_row
   ,encrypt
   ,compression
   ,deduplication
   ,securefile
   ,partitioned
   FROM  dba_lobs
WHERE  owner  =   ' TRBTKT '
ORDER   BY  table_name, column_name
;
TTITLE  OFF
-- 视图: DBA_PART_LOBS
-- 显示BasicFile和SecureFile LOB的默认值
TTITLE  ' BasicFile and SecureFile Partitioned LOB Default Settings|(from DBA_PART_LOBS) '
COL table_name          FORMAT A20      HEADING  ' Table '
COL column_name         FORMAT A12      HEADING  ' Column '
COL def_cache           FORMAT A12      HEADING  ' Cached '
COL def_tablespace_name FORMAT A12      HEADING  ' Tablespace '
COL def_securefile      FORMAT A12      HEADING  ' SecureFile '
COL def_encrypt         FORMAT A12      HEADING  ' Encrypted '
COL def_compress        FORMAT A12      HEADING  ' Compressed '
COL def_deduplicate     FORMAT A12      HEADING  ' DeDuplicated '
SELECT
    table_name
   ,column_name
   ,def_cache
   ,def_tablespace_name
   ,def_securefile
   ,def_compress
   ,def_deduplicate
   ,def_encrypt
   FROM  dba_part_lobs
WHERE  table_owner  =   ' TRBTKT '
ORDER   BY  table_name, column_name
;
TTITLE  OFF
-- 视图: DBA_LOB_PARTITIONS
-- 在独立的LOB级描述BasicFile和SecureFile设置
TTITLE  ' BasicFile and SecureFile LOB Partitions|(from DBA_LOB_PARTITIONS) '
COL table_name      FORMAT A16      HEADING  ' Table '
COL column_name     FORMAT A12      HEADING  ' Column '
COL partition_name  FORMAT A12      HEADING  ' Stored in|Partition '
COL cache           FORMAT A10      HEADING  ' Cacheing '
COL in_row          FORMAT A10      HEADING  ' Stored|In Row '
COL encrypt         FORMAT A10      HEADING  ' Encrypted '
COL compression     FORMAT A10      HEADING  ' Compressed '
COL deduplication   FORMAT A10      HEADING  ' DeDupli-|cated '
COL securefile      FORMAT A10      HEADING  ' SecureFile? '
SELECT
    table_name
   ,column_name
   ,partition_name
   ,cache
   ,in_row
   ,encrypt
   ,compression
   ,deduplication
   ,securefile
   FROM  dba_lob_partitions
WHERE  table_owner  =   ' TRBTKT '
ORDER   BY  table_name, column_name
;
TTITLE  OFF
报告1 从BasicFIle和SecureFile LOB元数据报告返回的结果
LOB段信息
                                                            (来自DBA_SEGMENTS)

                               Segment              Segment              Partition                                                          
Segment Name                   Type                 SubType              Name         Tablespace                                            
-- ----------------------- -------------------- -------------------- ------------ ------------                                          
SECURE_TICKETS                  TABLE  PARTITION      ASSM                 STS_PENDING  USERS                                                 
SECURE_TICKETS                  TABLE  PARTITION      ASSM                 STS_CLOSED   USERS                                                 
SECURE_TICKETS                  TABLE  PARTITION      ASSM                 STS_OPEN     USERS                                                 
SECURE_TICKETS                  TABLE  PARTITION      ASSM                 STS_OTHER    USERS                                                 
SYS_IL0000072118C00005$$        INDEX  PARTITION      ASSM                 SYS_IL_P180  BASICFILES                                            
SYS_IL0000072118C00005$$        INDEX  PARTITION      ASSM                 SYS_IL_P179  BASICFILES                                            
SYS_IL0000072118C00005$$        INDEX  PARTITION      ASSM                 SYS_IL_P178  BASICFILES                                            
SYS_IL0000072118C00005$$        INDEX  PARTITION      ASSM                 SYS_IL_P177  BASICFILES                                            
SYS_IL0000072118C00006$$        INDEX  PARTITION      ASSM                 SYS_IL_P185  BASICFILES                                            
SYS_IL0000072118C00006$$        INDEX  PARTITION      ASSM                 SYS_IL_P188  BASICFILES                                            
SYS_IL0000072118C00006$$        INDEX  PARTITION      ASSM                 SYS_IL_P187  BASICFILES                                            
SYS_IL0000072118C00006$$        INDEX  PARTITION      ASSM                 SYS_IL_P186  BASICFILES                                            
SYS_IL0000072144C00005$$        INDEX  PARTITION      ASSM                 SYS_IL_P194  SECUREFILES                                           
SYS_IL0000072144C00005$$        INDEX  PARTITION      ASSM                 SYS_IL_P193  SECUREFILES                                           
SYS_IL0000072144C00005$$        INDEX  PARTITION      ASSM                 SYS_IL_P195  SECUREFILES                                           
SYS_IL0000072144C00005$$        INDEX  PARTITION      ASSM                 SYS_IL_P196  SECUREFILES                                           
SYS_IL0000072144C00006$$        INDEX  PARTITION      ASSM                 SYS_IL_P204  SECUREFILES                                           
SYS_IL0000072144C00006$$        INDEX  PARTITION      ASSM                 SYS_IL_P203  SECUREFILES                                           
SYS_IL0000072144C00006$$        INDEX  PARTITION      ASSM                 SYS_IL_P202  SECUREFILES                                           
SYS_IL0000072144C00006$$        INDEX  PARTITION      ASSM                 SYS_IL_P201  SECUREFILES                                           
SYS_LOB0000072118C00005$$      LOB PARTITION        ASSM                 SYS_LOB_P173 BASICFILES                                            
SYS_LOB0000072118C00005$$      LOB PARTITION        ASSM                 SYS_LOB_P176 BASICFILES                                            
SYS_LOB0000072118C00005$$      LOB PARTITION        ASSM                 SYS_LOB_P175 BASICFILES                                            
SYS_LOB0000072118C00005$$      LOB PARTITION        ASSM                 SYS_LOB_P174 BASICFILES                                            
SYS_LOB0000072118C00006$$      LOB PARTITION        ASSM                 SYS_LOB_P184 BASICFILES                                            
SYS_LOB0000072118C00006$$      LOB PARTITION        ASSM                 SYS_LOB_P183 BASICFILES                                            
SYS_LOB0000072118C00006$$      LOB PARTITION        ASSM                 SYS_LOB_P181 BASICFILES                                            
SYS_LOB0000072118C00006$$      LOB PARTITION        ASSM                 SYS_LOB_P182 BASICFILES                                            
SYS_LOB0000072144C00005$$      LOB PARTITION        SECUREFILE           SYS_LOB_P191 SECUREFILES                                           
SYS_LOB0000072144C00005$$      LOB PARTITION        SECUREFILE           SYS_LOB_P192 SECUREFILES                                           
SYS_LOB0000072144C00005$$      LOB PARTITION        SECUREFILE           SYS_LOB_P189 SECUREFILES                                           
SYS_LOB0000072144C00005$$      LOB PARTITION        SECUREFILE           SYS_LOB_P190 SECUREFILES                                           
SYS_LOB0000072144C00006$$      LOB PARTITION        SECUREFILE           SYS_LOB_P198 SECUREFILES                                           
SYS_LOB0000072144C00006$$      LOB PARTITION        SECUREFILE           SYS_LOB_P199 SECUREFILES                                           
SYS_LOB0000072144C00006$$      LOB PARTITION        SECUREFILE           SYS_LOB_P197 SECUREFILES                                           
SYS_LOB0000072144C00006$$      LOB PARTITION        SECUREFILE           SYS_LOB_P200 SECUREFILES                                           
TICKETS                         TABLE  PARTITION      ASSM                 STS_PENDING  USERS                                                 
TICKETS                         TABLE  PARTITION      ASSM                 STS_OTHER    USERS                                                 
TICKETS                         TABLE  PARTITION      ASSM                 STS_OPEN     USERS                                                 
TICKETS                         TABLE  PARTITION      ASSM                 STS_CLOSED   USERS                                                 
TICKETS_PK_IDX                  INDEX                 ASSM                              USERS                                                 

                                                   BasicFile和SecureFile LOB元数据
                                                              (来自DBA_LOBS)

                                                                                      Stored  Encryp -  Compre -  DeDupli -  Secure  Parti -        
Table            Column      Segment                    Tablespace   Logging  Cacheing    In  Row  tion    ssion   cation    File ?   tioned       
-- ------------ ---------- -------------------------- ------------ -------- ---------- ------- ------- ------- -------- ------- -------      
SECURE_TICKETS DOCUMENT   SYS_LOB0000072118C00005$$  BASICFILES   NONE     NO         YES     NONE    NONE    NONE     NO      YES          
SECURE_TICKETS SCRNIMG    SYS_LOB0000072118C00006$$  BASICFILES   NONE     NO         YES     NONE    NONE    NONE     NO      YES          
TICKETS        DOCUMENT   SYS_LOB0000072144C00005$$  SECUREFILES  NONE     YES        NO      NO      NO      NO       YES     YES          
TICKETS        SCRNIMG    SYS_LOB0000072144C00006$$  SECUREFILES  NONE     CACHEREADS NO      NO      NO      NO       YES     YES          

                                         BasicFile和SecureFile分区LOB默认设置
                                                            (来自DBA_PART_LOBS)

Table       Column        Cached       Tablespace   SecureFile   Compressed   DeDuplicated Encrypted                                
-- --- ------------ ------------ ------------ ------------ ------------ ------------ ------------                             
SECURE_TICKETS     DOCUMENT     NO           BASICFILES   NO           NONE         NONE         NONE                                     
SECURE_TICKETS     SCRNIMG      NO           BASICFILES   NO           NONE         NONE         NONE                                     
TICKETS              DOCUMENT     YES          SECUREFILES  YES          NO           NO           NO                                       
TICKETS              SCRNIMG      CACHEREADS   SECUREFILES  YES          NO           NO           NO                                       

                                                  BasicFile和SecureFile LOB分区
                                                         (来自DBA_LOB_PARTITIONS)

                              Stored  in                Stored                           DeDupli -                                              
Table      Column      Partition    Cacheing    In  Row     Encrypted  Compressed cated      SecureFile                                
-- -- ------------ ------------ ---------- ---------- ---------- ---------- ---------- ----------                                
SECURE_TICKETS   DOCUMENT     STS_OTHER    NO         YES        NONE       NONE       NONE       NO                                        
SECURE_TICKETS   DOCUMENT     STS_CLOSED   NO         YES        NONE       NONE       NONE       NO                                        
SECURE_TICKETS   DOCUMENT     STS_OPEN     NO         YES        NONE       NONE       NONE       NO                                        
SECURE_TICKETS   DOCUMENT     STS_PENDING  NO         YES        NONE       NONE       NONE       NO                                        
SECURE_TICKETS   SCRNIMG      STS_OTHER    NO         YES        NONE       NONE       NONE       NO                                        
SECURE_TICKETS   SCRNIMG      STS_CLOSED   NO         YES        NONE       NONE       NONE       NO                                        
SECURE_TICKETS   SCRNIMG      STS_PENDING  NO         YES        NONE       NONE       NONE       NO                                        
SECURE_TICKETS   SCRNIMG      STS_OPEN     NO         YES        NONE       NONE       NONE       NO                                        
TICKETS          DOCUMENT     STS_OTHER    YES        NO         NO         HIGH       LOB        YES                                       
TICKETS          DOCUMENT     STS_PENDING  YES        NO         NO         NO         NO         YES                                       
TICKETS          DOCUMENT     STS_CLOSED   YES        NO         NO         MEDIUM     LOB        YES                                       
TICKETS          DOCUMENT     STS_OPEN     YES        NO         NO         NO         NO         YES                                       
TICKETS          SCRNIMG      STS_PENDING  CACHEREADS NO         NO         MEDIUM     LOB        YES                                       
TICKETS          SCRNIMG      STS_OPEN     CACHEREADS NO         NO         MEDIUM     NO         YES                                       
TICKETS          SCRNIMG      STS_CLOSED   CACHEREADS NO         NO         HIGH       LOB        YES                                       
TICKETS          SCRNIMG      STS_OTHER    CACHEREADS NO         NO         HIGH       LOB        YES

　2、DBMS_SPACE

　　这是另一个Oracle古老支持包，它的SPACE_USAGE存储过程提供关于BasicFile和SecureFile LOB的空间利用率，我在TRBTKT.PKG_SECUREFILES包中引入了两个存储过程：CALC_SPACE_BASICFILES和CALC_SPACE_SECUREFILES。但遗憾的是，这个功能只能在启用了自动段空间管理(ASSM)的表空间上使用，而且，它也不会考虑任何BasicFile LOB块的空间利用率，在清单5中，我对表TRBTKT.TICKETS和TRBTKT.SECURE_TICKETS分别调用了这些存储过程，并返回了相应的输出。

　　清单5 确定BasicFile和SecureFile LOB的空间利用率

SET  SERVEROUTPUT  ON
--  BasicFile存储利用率:
BEGIN
    trbtkt.pkg_securefiles.calc_space_basicfiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' SECURE_TICKETS '
        ,colname  =>   ' DOCUMENT '
        ,partname  =>   ' STS_OPEN '
    );
    trbtkt.pkg_securefiles.calc_space_basicfiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' SECURE_TICKETS '
        ,colname  =>   ' DOCUMENT '
        ,partname  =>   ' STS_PENDING '
    );
    trbtkt.pkg_securefiles.calc_space_basicfiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' SECURE_TICKETS '
        ,colname  =>   ' DOCUMENT '
        ,partname  =>   ' STS_CLOSED '
    );
    trbtkt.pkg_securefiles.calc_space_basicfiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' SECURE_TICKETS '
        ,colname  =>   ' DOCUMENT '
        ,partname  =>   ' STS_OTHER '
    );
    trbtkt.pkg_securefiles.calc_space_basicfiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' SECURE_TICKETS '
        ,colname  =>   ' SCRNIMG '
        ,partname  =>   ' STS_OPEN '
    );
    trbtkt.pkg_securefiles.calc_space_basicfiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' SECURE_TICKETS '
        ,colname  =>   ' SCRNIMG '
        ,partname  =>   ' STS_PENDING '
    );
    trbtkt.pkg_securefiles.calc_space_basicfiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' SECURE_TICKETS '
        ,colname  =>   ' SCRNIMG '
        ,partname  =>   ' STS_CLOSED '
    );
    trbtkt.pkg_securefiles.calc_space_basicfiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' SECURE_TICKETS '
        ,colname  =>   ' SCRNIMG '
        ,partname  =>   ' STS_OTHER '
    );
END ;
/
============================================================
Space  Usage  for  BasicFile LOB TRBTKT.SECURE_TICKETS.DOCUMENT
Partition Name: STS_OPEN                                    
-- ----------------------------------------------------------
Full  Blocks:  123  KB: . 96                                     
Unformatted Blocks:  379  KB:  2.96                             
Total Blocks:  123  Total KB: . 96                              
============================================================
============================================================
Space  Usage  for  BasicFile LOB TRBTKT.SECURE_TICKETS.DOCUMENT
Partition Name: STS_PENDING                                 
-- ----------------------------------------------------------
Full  Blocks:  20  KB: . 16                                      
Unformatted Blocks:  482  KB:  3.77                             
Total Blocks:  20  Total KB: . 16                               
============================================================
============================================================
Space  Usage  for  BasicFile LOB TRBTKT.SECURE_TICKETS.DOCUMENT
Partition Name: STS_CLOSED                                  
-- ----------------------------------------------------------
Full  Blocks:  37  KB: . 29                                      
Unformatted Blocks:  465  KB:  3.63                             
Total Blocks:  37  Total KB: . 29                               
============================================================
============================================================
Space  Usage  for  BasicFile LOB TRBTKT.SECURE_TICKETS.DOCUMENT
Partition Name: STS_OTHER                                   
-- ----------------------------------------------------------
Full  Blocks:  0  KB:  0                                         
Unformatted Blocks:  0  KB:  0                                  
Total Blocks:  0  Total KB:  0                                  
============================================================
============================================================
Space  Usage  for  BasicFile LOB TRBTKT.SECURE_TICKETS.SCRNIMG 
Partition Name: STS_OPEN                                    
-- ----------------------------------------------------------
Full  Blocks:  420  KB:  3.28                                    
Unformatted Blocks:  82  KB: . 64                               
Total Blocks:  420  Total KB:  3.28                             
============================================================
============================================================
Space  Usage  for  BasicFile LOB TRBTKT.SECURE_TICKETS.SCRNIMG 
Partition Name: STS_PENDING                                 
-- ----------------------------------------------------------
Full  Blocks:  66  KB: . 52                                      
Unformatted Blocks:  436  KB:  3.41                             
Total Blocks:  66  Total KB: . 52                               
============================================================
============================================================
Space  Usage  for  BasicFile LOB TRBTKT.SECURE_TICKETS.SCRNIMG 
Partition Name: STS_CLOSED                                  
-- ----------------------------------------------------------
Full  Blocks:  144  KB:  1.13                                    
Unformatted Blocks:  358  KB:  2.8                              
Total Blocks:  144  Total KB:  1.13                             
============================================================
============================================================
Space  Usage  for  BasicFile LOB TRBTKT.SECURE_TICKETS.SCRNIMG 
Partition Name: STS_OTHER                                   
-- ----------------------------------------------------------
Full  Blocks:  0  KB:  0                                         
Unformatted Blocks:  0  KB:  0                                  
Total Blocks:  0  Total KB:  0                                  
============================================================
--  SecureFile存储利用率:
BEGIN
    trbtkt.pkg_securefiles.calc_space_securefiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' TICKETS '
        ,colname  =>   ' DOCUMENT '
        ,partname  =>   ' STS_OPEN '
    );
    trbtkt.pkg_securefiles.calc_space_securefiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' TICKETS '
        ,colname  =>   ' DOCUMENT '
        ,partname  =>   ' STS_PENDING '
    );
    trbtkt.pkg_securefiles.calc_space_securefiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' TICKETS '
        ,colname  =>   ' DOCUMENT '
        ,partname  =>   ' STS_CLOSED '
    );
    trbtkt.pkg_securefiles.calc_space_securefiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' TICKETS '
        ,colname  =>   ' DOCUMENT '
        ,partname  =>   ' STS_OTHER '
    );
    trbtkt.pkg_securefiles.calc_space_securefiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' TICKETS '
        ,colname  =>   ' SCRNIMG '
        ,partname  =>   ' STS_OPEN '
    );
    trbtkt.pkg_securefiles.calc_space_securefiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' TICKETS '
        ,colname  =>   ' SCRNIMG '
        ,partname  =>   ' STS_PENDING '
    );
    trbtkt.pkg_securefiles.calc_space_securefiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' TICKETS '
        ,colname  =>   ' SCRNIMG '
        ,partname  =>   ' STS_CLOSED '
    );
    trbtkt.pkg_securefiles.calc_space_securefiles (
         ownname  =>   ' TRBTKT '
        ,tabname  =>   ' TICKETS '
        ,colname  =>   ' SCRNIMG '
        ,partname  =>   ' STS_OTHER '
    );
END ;
/

============================================================
Space  Usage  for  SecureFile LOB TRBTKT.TICKETS.DOCUMENT      
Partition Name: STS_OPEN                                    
-- ----------------------------------------------------------
Segment Blocks:  1024  KB:  8192                                
Used Blocks:  124  KB:  992                                     
Expired Blocks:  882  KB:  7056                                 
Unexpired Blocks:  0  KB:  0                                    
============================================================
============================================================
Space  Usage  for  SecureFile LOB TRBTKT.TICKETS.DOCUMENT      
Partition Name: STS_PENDING                                 
-- ----------------------------------------------------------
Segment Blocks:  1024  KB:  8192                                
Used Blocks:  21  KB:  168                                      
Expired Blocks:  985  KB:  7880                                 
Unexpired Blocks:  0  KB:  0                                    
============================================================
============================================================
Space  Usage  for  SecureFile LOB TRBTKT.TICKETS.DOCUMENT      
Partition Name: STS_CLOSED                                  
-- ----------------------------------------------------------
Segment Blocks:  1024  KB:  8192                                
Used Blocks:  13  KB:  104                                      
Expired Blocks:  993  KB:  7944                                 
Unexpired Blocks:  0  KB:  0                                    
============================================================
============================================================
Space  Usage  for  SecureFile LOB TRBTKT.TICKETS.DOCUMENT      
Partition Name: STS_OTHER                                   
-- ----------------------------------------------------------
Segment Blocks:  512  KB:  4096                                 
Used Blocks:  501  KB:  4008                                    
Expired Blocks:  0  KB:  0                                      
Unexpired Blocks:  0  KB:  0                                    
============================================================
============================================================
Space  Usage  for  SecureFile LOB TRBTKT.TICKETS.SCRNIMG       
Partition Name: STS_OPEN                                    
-- ----------------------------------------------------------
Segment Blocks:  2560  KB:  20480                               
Used Blocks:  405  KB:  3240                                    
Expired Blocks:  2134  KB:  17072                               
Unexpired Blocks:  0  KB:  0                                    
============================================================
============================================================
Space  Usage  for  SecureFile LOB TRBTKT.TICKETS.SCRNIMG       
Partition Name: STS_PENDING                                 
-- ----------------------------------------------------------
Segment Blocks:  1024  KB:  8192                                
Used Blocks:  62  KB:  496                                      
Expired Blocks:  944  KB:  7552                                 
Unexpired Blocks:  0  KB:  0                                    
============================================================
============================================================
Space  Usage  for  SecureFile LOB TRBTKT.TICKETS.SCRNIMG       
Partition Name: STS_CLOSED                                  
-- ----------------------------------------------------------
Segment Blocks:  1024  KB:  8192                                
Used Blocks:  142  KB:  1136                                    
Expired Blocks:  864  KB:  6912                                 
Unexpired Blocks:  0  KB:  0                                    
============================================================
============================================================
Space  Usage  for  SecureFile LOB TRBTKT.TICKETS.SCRNIMG       
Partition Name: STS_OTHER                                   
-- ----------------------------------------------------------
Segment Blocks:  512  KB:  4096                                 
Used Blocks:  501  KB:  4008                                    
Expired Blocks:  0  KB:  0                                      
Unexpired Blocks:  0  KB:  0                                    
============================================================
SET  SERVEROUTPUT  ON

修改SecureFile属性

　　当我创建TRBTKT.SECURE_TICKETS表时，你可能注意到我为每个LOB列在它们对应的分区中执行压缩和重复删除，重要的是我还使用了ALTER TABLE语句进行修正，另外，如果需要的话，我还可以在每个LOB独立的分区上应用改变到SecureFile LOB。清单6中的代码显示了4个修改TRBTKT.TICKETS表的SecureFile LOB属性的例子，注意这个表现在已经用清单3中的代码和TRBTKT.SECURE_TICKETS表执行了交换，我也从DBA_PART_LOBS创建了一个报告显示在修改这些LOB属性前后的状态，结果输出如报告2所示。

　　清单6 管理SecureFile LOB属性

SQL >   ALTER   TABLE  TRBTKT.TICKETS
SQL >      MODIFY LOB(DOCUMENT) (NOCOMPRESS);

Table  altered.


SQL >   ALTER   TABLE  TRBTKT.TICKETS
SQL >      MODIFY LOB(SCRNIMG) (KEEP_DUPLICATES);

Table  altered.

SQL >   ALTER   TABLE  TRBTKT.TICKETS
SQL >      MODIFY PARTITION STS_PENDING LOB(SCRNIMG) (COMPRESS HIGH);
                                                                      
Table  altered.
                                                                      
SQL >   ALTER   TABLE  TRBTKT.TICKETS
SQL >      MODIFY PARTITION STS_PENDING LOB(DOCUMENT) (DEDUPLICATE);
                                                                      
Table  altered.

报告2 修改许多SecureFile LOB后查询DBA_LOB_PARTITIONS返回的结果

  BasicFile  and  SecureFile LOB Partitions
                                                         ( from  DBA_LOB_PARTITIONS)
                              Stored  in                Stored                           DeDupli -
Table              Column        Partition    Cacheing    In  Row     Encrypted  Compressed cated      SecureFile
-- -------------- ------------ ------------ ---------- ---------- ---------- ---------- --------
SECURE_TICKETS   DOCUMENT     STS_OTHER    NO         YES        NONE       NONE       NONE       NO
SECURE_TICKETS   DOCUMENT     STS_CLOSED   NO         YES        NONE       NONE       NONE       NO
SECURE_TICKETS   DOCUMENT     STS_OPEN     NO         YES        NONE       NONE       NONE       NO
SECURE_TICKETS   DOCUMENT     STS_PENDING  NO         YES        NONE       NONE       NONE       NO
SECURE_TICKETS   SCRNIMG      STS_OTHER    NO         YES        NONE       NONE       NONE       NO
SECURE_TICKETS   SCRNIMG      STS_CLOSED   NO         YES        NONE       NONE       NONE       NO
SECURE_TICKETS   SCRNIMG      STS_PENDING  NO         YES        NONE       NONE       NONE       NO
SECURE_TICKETS   SCRNIMG      STS_OPEN     NO         YES        NONE       NONE       NONE       NO
TICKETS          DOCUMENT     STS_OTHER    YES        NO         NO         NO         LOB        YES
TICKETS          DOCUMENT     STS_PENDING  YES        NO         NO         NO         LOB        YES
TICKETS          DOCUMENT     STS_CLOSED   YES        NO         NO         NO         LOB        YES
TICKETS          DOCUMENT     STS_OPEN     YES        NO         NO         NO         NO         YES
TICKETS          SCRNIMG      STS_PENDING  CACHEREADS NO         NO         HIGH       NO         YES
TICKETS          SCRNIMG      STS_OPEN     CACHEREADS NO         NO         MEDIUM     NO         YES
TICKETS          SCRNIMG      STS_CLOSED   CACHEREADS NO         NO         HIGH       NO         YES
TICKETS          SCRNIMG      STS_OTHER    CACHEREADS NO         NO         HIGH       NO         YES

         最后，请记住任何对LOB属性进行修改都只会影响到新创建的LOB或新修改的LOB，例如，将列TRBTKT.SECURE_TICKETS.SCRNIMG的压缩方法从COMPRESS修改为NOCOMPRESS不会影响到现有的LOB条目。