Use expdp/impdp to reorganize a tablespace to remove additional datafile ?

Question

Oracle 10g (10.2.0.1)
We had a tablespace with a single datafile WORK1, WORK1 filled up, colleague added two datafiles WORK2 and WORK3 (instead of resizing original larger).
I resized WORK1, increasing by 500Mb.
I was able to drop WORK3, but not WORK2 (ORA-03262: the file is non-empty)
My proposed solution is to expdp the tablespace, drop the tablespace and datafiles, recreate the tablespace with a correctly sized datafile and finally impdp the tablespace.
Is this solution valid ?
Any hints at syntax would be useful

Answer 1

1. Map your datafile.
2. If no segments in datafile, drop it and go to 5.
2. Shrink the datafile up to where the data ends.
3. Rebuild/move the last object in the data file,
4. Go to 1
5. Fin
To map data file...
accept file_num char prompt 'File ID: ';
SET PAGESIZE   70
SET LINESIZE   132
SET NEWPAGE    0
SET VERIFY     OFF
SET ECHO       OFF
SET HEADING    ON
SET FEEDBACK   OFF
SET TERMOUT    ON
COLUMN file_name   FORMAT a50          HEADING 'File Name'
COLUMN owner       FORMAT a10   TRUNC  HEADING 'Owner'
COLUMN object      FORMAT a30   TRUNC  HEADING 'Object'
COLUMN obj_type    FORMAT a2           HEADING ' '
COLUMN block_id    FORMAT 9999999      HEADING 'Block|ID'
COLUMN blocks      FORMAT 999,999      HEADING 'Blocks'
COLUMN mbytes      FORMAT 9,999.99     HEADING 'M-Bytes'
SELECT  'free space'      owner,
        ' '               object,
        ' '               obj_type,
        f.file_name,
        s.block_id,
        s.blocks,
        s.bytes/1048576   mbytes
  FROM  dba_free_space s,
        dba_data_files f
WHERE  s.file_id = TO_NUMBER(&file_num)
   AND  s.file_id = f.file_id
UNION
SELECT  owner,
        segment_name,
        DECODE(segment_type, 'TABLE',          'T',
                             'INDEX',          'I',
                             'ROLLBACK',       'RB',
                             'CACHE',          'CH',
                             'CLUSTER',        'CL',
                             'LOBINDEX',       'LI',
                             'LOBSEGMENT',     'LS',
                             'TEMPORARY',      'TY',
                             'NESTED TABLE',   'NT',
                             'TYPE2 UNDO',     'U2',
                             'TABLE PARTITION','TP',
                             'INDEX PARTITION','IP', '?'),
        f.file_name,
        s.file_id,
        s.block_id,
        s.blocks,
        s.bytes/1048576
  FROM  dba_extents s,
        dba_data_files f
WHERE  s.file_id = TO_NUMBER(&file_num)
   AND  s.file_id = f.file_id
ORDER
    BY  file_id,
        block_id