Oracle中，對錶上的lob欄位是單獨儲存的，所以使用segment_name = 表名的時候，只能統計非 lob 欄位的資料大小，無法統計上lob欄位的。

　　為了方面統計，在MOS上找到一篇參考文章：

How to Compute the Size of a Table containing Outline CLOBs and BLOBs (文件 ID 118531.1)

相關的SQL語句如下：

SELECT
 (SELECT SUM(S.BYTES)                                                                                                                   
 
-- The Table Segment size
  FROM DBA_SEGMENTS S
  WHERE S.OWNER = UPPER('&SCHEMA') AND
       (S.SEGMENT_NAME = UPPER('&TABNAME'))) +  (SELECT SUM(S.BYTES)                                                 　　　　　　　　　　　 -- The Lob Segment Size
  FROM DBA_SEGMENTS S, DBA_LOBS L
  WHERE S.OWNER = UPPER('
 
&SCHEMA') AND
       (L.SEGMENT_NAME = S.SEGMENT_NAME AND L.TABLE_NAME = UPPER('&TABNAME') AND L.OWNER = UPPER('&SCHEMA'))) +  (SELECT SUM(S.BYTES)    -- The Lob Index size
  FROM DBA_SEGMENTS S, DBA_INDEXES I
  WHERE S.OWNER = UPPER('&SCHEMA') AND
       (I.INDEX_NAME = S.SEGMENT_NAME AND I.TABLE_NAME = UPPER('
 
&TABNAME') AND INDEX_TYPE = 'LOB' AND I.OWNER = UPPER('&SCHEMA')))
  "TOTAL TABLE SIZE"
FROM DUAL;