SQL & PL/SQL :: How To Release Storage When Truncating Partition

assuption is that when we truncate the partition it immediatly release the allocatd storage.i have just tested the scenario , but still i can see that table size is same even after truncating the partition( which have around 25% of the data)

alter table test truncate partition t1p3 update indexes ;

OR

alter table test truncate partition t1p3 drop storage update indexes ; to see the table size:

SELECT owner, table_name, TRUNC(sum(bytes) / 1024 / 1024) Meg
FROM (SELECT segment_name table_name, owner, bytes
FROM dba_segments
WHERE segment_type = 'TABLE'
UNION ALL
[code]...