Indexed access for INET/ CIDR datatype

I don't think so. Those operators aren't total orders and I think btree
will only work with total orders. I expect that it should be possible
to develop rtree or gist indexes though.

There are some provisions for turning <<= tests into range scans,
for example

regression=# create table foo (f1 inet unique);
NOTICE: CREATE TABLE / UNIQUE will create implicit index 'foo_f1_key' for table 'foo'
CREATE TABLE
regression=# explain select * from foo where f1 <<= '127.0/16';
QUERY PLAN
--------------------------------------------------------------------------------
Index Scan using foo_f1_key on foo (cost=0.00..17.07 rows=500 width=32)
Index Cond: ((f1 >= '127.0.0.0/16'::inet) AND (f1 <= '127.0.255.255'::inet))
Filter: (f1 <<= '127.0.0.0/16'::inet)
(3 rows)

I believe you have to write "field <<= constant" to get this to happen.

regards, tom lane

Thanks Mark, so creating a unique constraint, as opposed to a unique index
makes a difference to the query plan. I noticed one thing though :

My table has an entry like '24.128.168.0/23' in the INET datatype
field. I'm trying to do a lookup for '24.128.168.61' which is contained in
the above:
explain select * from iptest2 where ip >>= '24.128.168.61'
yields
Seq Scan on iptest2 (cost=0.00..22.50 rows-500 width=32)
Filter (ip >>='24.128.168.61'::inet)

I was hoping that, by using the INET datatype, I could do lookups of
individual IPs against a range efficiently, but that doesn't seem to be the
case.

If I try to create a rtree index, I get the error :

Number: -2147467259
Description: ERROR: data type inet has no default operator class for
access method "rtree". You must specify an operator class for the
index or define a default operator clas for the data type

Any idea how to get around that?

Thanks and regards


Ananth


-----Original Message-----
From: Tom Lane
Sent: Thursday, June 19, 2003 1:58 PM
To: Bruno Wolff III
Cc: Kaitharam, Ananth; '[email protected]'
Subject: Re: [NOVICE] Indexed access for INET/ CIDR datatype

Bruno Wolff III <[email protected]> writes:
datatypes? I
There are some provisions for turning <<= tests into range scans,
for example

regression=# create table foo (f1 inet unique);
NOTICE: CREATE TABLE / UNIQUE will create implicit index 'foo_f1_key' for
table 'foo'
CREATE TABLE
regression=# explain select * from foo where f1 <<= '127.0/16';
QUERY PLAN
----------------------------------------------------------------------------
----
Index Scan using foo_f1_key on foo (cost=0.00..17.07 rows=500 width=32)
Index Cond: ((f1 >= '127.0.0.0/16'::inet) AND (f1 <=
'127.0.255.255'::inet))
Filter: (f1 <<= '127.0.0.0/16'::inet)
(3 rows)

I believe you have to write "field <<= constant" to get this to happen.

regards, tom lane

This just came up today in another thread and the answer is that if you
use a btree index a range scan over the index will be used.