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    Name:    tabused.sql

    This script lists the percentage of storage that a table 
    is using. You will be required to enter the table name.

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ttitle 'Table Percent Used'

SELECT   BLOCKS                                   ALLOCATED_BLKS,
         COUNT(DISTINCT SUBSTR(T.ROWID,1,8) 
                         || SUBSTR(T.ROWID,15,4))     USED, 
         (COUNT(DISTINCT SUBSTR(T.ROWID,1,8) 
                         || SUBSTR(T.ROWID,15,4)) 
             / BLOCKS) * 100                          PCT_USED
  FROM    SYS.DBA_SEGMENTS E,
          &TAB_NAME T
 WHERE    E.SEGMENT_NAME = UPPER ('&TAB_NAME')
   AND    E.SEGMENT_TYPE = 'TABLE' 
 GROUP BY E.BLOCKS;