Table Reorganization (reclaim space)

This shows that "alter table x move" reclaims the space.
As seen here in: http://www.dba-oracle.com/t_alter_table_move_shrink_space.htm
It says it doesn't change the table size.


SQL> begin
2 for i in 1..1000000 loop
3 insert into audadm.t1 values (i);
4 end loop;
5 commit;
6 end;
7 /

PL/SQL procedure successfully completed.

SQL> analyze table audadm.t1 compute statistics;

Table analyzed.

SQL> select blocks,empty_blocks,num_rows from dba_tables where table_name='T1';

BLOCKS EMPTY_BLOCKS NUM_ROWS
---------- ------------ ----------
2276 1819 1500000

SQL> select blocks, extents from dba_segments where segment_name='T1';

BLOCKS EXTENTS
---------- ----------
4096 2

SQL> select sum(bytes) from dba_segments where segment_name = 'T1';

SUM(BYTES)
----------
33554432

SQL> delete from audadm.t1 where mod(x,2)=0;

500000 rows deleted.

SQL> commit;

Commit complete.

SQL> analyze table audadm.t1 compute statistics;

Table analyzed.

SQL> select blocks,empty_blocks,num_rows from dba_tables where table_name='T1';

BLOCKS EMPTY_BLOCKS NUM_ROWS
---------- ------------ ----------
2276 1819 1000000

SQL> select blocks, extents from dba_segments where segment_name='T1';

BLOCKS EXTENTS
---------- ----------
4096 2

SQL> select sum(bytes) from dba_segments where segment_name = 'T1';

SUM(BYTES)
----------
33554432

SQL> alter table audadm.t1 move;

Table altered.

SQL> analyze table audadm.t1 compute statistics;

Table analyzed.

SQL> select blocks,empty_blocks,num_rows from dba_tables where table_name='T1';

BLOCKS EMPTY_BLOCKS NUM_ROWS
---------- ------------ ----------
1520 527 1000000

SQL> select blocks, extents from dba_segments where segment_name='T1';

BLOCKS EXTENTS
---------- ----------
2048 1

SQL> select sum(bytes) from dba_segments where segment_name = 'T1';

SUM(BYTES)
----------
16777216

SQL>