数据库不能open的时候,可以通过dul挖取相关基表(user$,obj$,ts$,tab$,seg$,file$),从而来获得segment header信息,然后通过dump该block,结合shell脚本获得extents分布脚本来获得extent分布

   SELECT NVL (u.name, 'SYS'),
          o.name,
          o.subname,
          so.object_type,
          s.type#,
          DECODE (BITAND (s.spare1, 2097408),
                  2097152, 'SECUREFILE',
                  256, 'ASSM',
                  'MSSM'),
          ts.ts#,
          ts.name,
          ts.blocksize,
          f.file#,
          s.block#,
          s.blocks * ts.blocksize,
          s.blocks,
          s.extents,
          s.iniexts * ts.blocksize,
          s.extsize * ts.blocksize,
          s.minexts,
          s.maxexts,
          DECODE (BITAND (s.spare1, 4194304), 4194304, bitmapranges, NULL),
          TO_CHAR (
             DECODE (
                BITAND (s.spare1, 2097152),
                2097152, DECODE (s.lists,
                                 0, 'NONE',
                                 1, 'AUTO',
                                 2, 'MIN',
                                 3, 'MAX',
                                 4, 'DEFAULT',
                                 'INVALID'),
                NULL)),
          DECODE (BITAND (s.spare1, 2097152), 2097152, s.groups, NULL),
          DECODE (BITAND (ts.flags, 3), 1, TO_NUMBER (NULL), s.extpct),
          DECODE (BITAND (ts.flags, 32),
                  32, TO_NUMBER (NULL),
                  DECODE (s.lists, 0, 1, s.lists)),
          DECODE (BITAND (ts.flags, 32),
                  32, TO_NUMBER (NULL),
                  DECODE (s.groups, 0, 1, s.groups)),
          s.file#,
          BITAND (s.cachehint, 3),
          BITAND (s.cachehint, 12) / 4,
          BITAND (s.cachehint, 48) / 16,
          NVL (s.spare1, 0),
          o.dataobj#
     FROM chf.user$ u,
          chf.obj$ o,
          chf.ts$ ts,
          ( SELECT DECODE (BITAND (t.property, 8192), 8192, 'NESTED TABLE', 'TABLE') OBJECT_TYPE,
          2 OBJECT_TYPE_ID,
          5 SEGMENT_TYPE_ID,
          t.obj# OBJECT_ID,
          t.file# HEADER_FILE,
          t.block# HEADER_BLOCK,
          t.ts# TS_NUMBER
     FROM chf.tab$ t) so,
          chf.seg$ s,
          chf.file$ f
    WHERE     s.file# = so.header_file
          AND s.block# = so.header_block
          AND s.ts# = so.ts_number
          AND s.ts# = ts.ts#
          AND o.obj# = so.object_id
          AND o.owner# = u.user#(+)
          AND s.type# = so.segment_type_id
          AND o.type# = so.object_type_id
          AND s.ts# = f.ts#
          AND s.file# = f.relfile#
          and o.name in('XIFENFEI','T_XIFENFEI');