Syntax options:
ENABLE COMPRESSION | DISABLE COMPRESSION
Changes whether the rows for the table are compressed or
uncompressed when stored. Enabling compression conserves disk
space, but it incurs additional CPU overhead for inserting and
retrieving compressed rows.
Changing the COMPRESSION clause causes the database system
to read all the rows in the table and write them back to the
table in the changed format. If compression is enabled and you
subsequently disable it, records may become fragmented because
the space allowed for the record is no longer large enough.