network address query

Hi,

I have query:
explain
SELECT *
FROM ip_tracking T, ip_map C
WHERE
T.source_ip::inet >>= C.net;
QUERY PLAN
-------------------------------------------------------------------------------------------
Nested Loop (cost=0.00..3894833367750.16
rows=51709297065144 width=111)
Join Filter: ("outer".source_ip >>=
("inner".net)::inet)
-> Seq Scan on ip_tracking t
(cost=0.00..825050.68 rows=31093368 width=34)
-> Seq Scan on ip_map c (cost=0.00..83686.66
rows=3326066 width=77)
(4 rows)

ip_tracking (
pk_col int,
source_ip inet,
.. the rest...
)
There is one index
ip_tracking_ip_idx btree (source_ip)

ip_map (
net cidr,
... the rest...)
Indexes: map_net_idx hash (net)

If I change ">>=" to "=", the query plan is:

QUERY PLAN
--------------------------------------------------------------------------------------------------------------------------
Nested Loop (cost=0.00..10798882243.63 rows=31093368
width=111)
-> Seq Scan on ip_map c (cost=0.00..83686.66
rows=3326066 width=77)
-> Index Scan using ip_tracking_ip_idx on
ip_tracking t (cost=0.00..3236.72 rows=800 width=34)
Index Cond: (t.source_ip =
("outer".net)::inet)
(4 rows)

This is my first time to deal network address type.

Is it possible to make a query use index with
operator of ">>=" like the above?

Thanks,

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