Sep 162013
 
create cluster your_data_together (
  for_super_efficient_access integer
);

create table when_i_am_frequently_queried (
  and_performance_matters    varchar2(1) 
                               default 'Y',
  for_super_efficient_access integer
)
cluster your_data_together (
  for_super_efficient_access
);

create table and_joined_to_me (
  clustering_places_us_in    integer,
  the_same_physical_location integer,
  for_super_efficient_access integer
)
cluster your_data_together (
  for_super_efficient_access
);
Not to be confused with RAC (real application clusters), table clusters can 
be used to locate records with a common key into one place. This saves some
space as the cluster key is only stored once for all the tables in it. The 
bigger advantage is that all the tables in a cluster are physically located 
in the same place, so joins between these tables require fewer I/O operations 
than the equivalent heap tables.

If you’d like to know more, then have a look at the documentation or Iggy Fernandez has an example here (scroll to the “Appendix” section)

 Leave a Reply

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

(required)

(required)