How to shrink tables and indexes

1.Find out which tables and indexes can be shrunk.
SQL>select * from table(dbms_space.asa_recommendations('FALSE', 'FALSE',
'FALSE')) order by reclaimable_space desc;

2. Enable row movement.
SQL>ALTER TABLE table_name ENABLE ROW MOVEMENT;

3.Shrink the tables and associated indexes.
SQL>ALTER TABLE table_name SHRINK SPACE CASCADE;

4.Disable row movement.
SQL>ALTER TABLE table_name DISABLE ROW MOVEMENT;

5. Rebuild indexes.
SQL>alter index index_name rebuild;

Important Note: If you are performing this against 10.2.0.2 or 10.2.0.3 with cascade, be sure that you applied patch 5636728 before you shrink the tables and indexes. Otherwise LOBs that may in the table may get corrupt and there is no way to fix them!