db_keep_cche_size=512M
db_recycle_cache_size = 512M 

Alter table REF_ETL_GEOG_LOC_CD storage (buffer_pool keep)

SQL> select segment_name, segment_type, buffer_pool from dba_segments where segment_name = 'OFSA_LEAF_DESC' ;

SEGMENT_NAME         SEGMENT_TYPE       BUFFER_
-------------------- ------------------ -------
OFSA_LEAF_DESC       TABLE              KEEP

SQL> select buffer_pool, cache from dba_tables where owner = 'BOIDW' and table_name = 'OFSA_LEAF_DESC' ;

BUFFER_ CACHE
------- -----
KEEP        N

SQL>

Alter table OFSA_LEAF_DESC storage (buffer_pool KEEP)

select
   o.owner          owner,
   o.object_name    object_name,
   o.subobject_name subobject_name,
   o.object_type    object_type,
   count(distinct file# || block#)         num_blocks
from
   dba_objects  o,
   v$bh         bh
where
   o.data_object_id  = bh.objd
and   o.owner not in ('SYS','SYSTEM')
and   bh.status != 'free'
group by
   o.owner,
   o.object_name,
   o.subobject_name,
   o.object_type
order by   count(distinct file# || block#) desc

Alter table OFSA_LEAF_DESC storage (buffer_pool KEEP)

Alter table OFSA_LEAF_DESC Cache