How to add a default ADO compression policy to a tablespace

Create the tablespace:

CREATE BIGFILE TABLESPACE DATA1 DATAFILE
  '/oradata/mydb/data1.dbf' SIZE 1024M AUTOEXTEND ON NEXT 256M MAXSIZE 2T
DEFAULT
COMPRESS FOR OLTP
EXTENT MANAGEMENT LOCAL AUTOALLOCATE
SEGMENT SPACE MANAGEMENT AUTO
DEFAULT ILM ADD POLICY 
COMPRESS FOR ALL OPERATIONS 
GROUP 
AFTER 1 DAYS OF NO ACCESS;

Notice the "GROUP" keyword. It states the scope of an ADO policy, and can be a group of related objects, segment level or row-level, indicated by the keywords GROUP, ROW, or SEGMENT.

According to the documentation, by default, this will give you advanced compression on heap tables, standard compression for indexes and LOW for LOB segments created in the tablespace.

Any table created in this tablespace from now on will now inherit the ADO policy. Let's see it in action:

create table sh.test_ado_tabspc_compression as select * from sh.sales;

Table created.

Verify:

SELECT policy_name,
       object_owner,
       object_name,
       subobject_name,
       object_type,
       inherited_from,
       enabled,
       deleted
FROM   dba_ilmobjects
WHERE  object_owner='SH'
AND    object_name='SALES'
ORDER BY 1;

Result:

POLICY_NAME	OBJECT_OWNER	OBJECT_NAME	SUBOBJECT_NAME	OBJECT_TYPE	INHERITED_FROM	ENABLED	DELETED
P43	SH	TEST_ADO_TABSPC_COMPRESSION		TABLE	TABLESPACE	YES	NO

The table has inherited the ADO policy from the tablespace it was created in.