DB Wiki

By default the Heat Map initialisation parameter is set to OFF.
It can be changed at the session and system level.

 ALTER SYSTEM SET HEAT_MAP = ON;

Causes the database to track read and write access of all segments.
The activities are not tracked for objects in SYSTEM and SYSAUX tablespaces.

V$HEAT_MAP_SEGMENT
DBA_HEAT_MAP_SEGMENT
DBA_HEAT_MAP_TOP_OBJECTS
DBA_HEAT_MAP_TOP_TABLESPACES

ADO policies can be set at row, segment or tablespace level.
These policies will be evaluated automatically during the weekend maintenance window.

The commands are used in conjunction with the CREATE and ALTER TABLE commands

Compress Rows if they haven't been accessed for 60 days

ILM ADD POLICY 
ROW STORE COMPRESS ADVANCED 
SEGMENT AFTER 60 DAYS OF NO ACCESS;

Compress Rows 1 year after they have been created

ILM ADD POLICY
ROW STORE COMPRESS ADVANCED
SEGMENT AFTER 1 YEARS OF CREATION;

Compress Rows if they haven't been changed for 45 days

ILM ADD POLICY
ROW STORE COMPRESS ADVANCED
SEGMENT AFTER 45 DAYS OF NO MODIFICATION;

There can only be one row level policy for a segment.
The view USER_ILMPOLICIES shows details of all existing ADO policies.

Disable all ADO policies for the whole database

BEGIN
DBMS_ILM_ADMIN.DISABLE_ILM;
END;

Disable a single policy on a table

ALTER TABLE t1 ILM DISABLE_ALL;
ALTER TABLE t1 ILM disable <policy_name>;