Date: Mon, 17 Sep 2007 10:43:24 -0400
From: Andrew Sullivan <ajs@crankycanuck.ca>
To: pgsql-sql@postgresql.org
Subject: Re: Extracting hostname from URI column
Message-ID: <20070917144324.GP582@crankycanuck.ca>
References: <335491.75226.qm@web54303.mail.re2.yahoo.com>
	<46E73D1C.4020009@autoledgers.com.au>
	<46EDB43D.9060405@autoledgers.com.au>
	<873axekxlr.fsf@oxford.xeocode.com>
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On Mon, Sep 17, 2007 at 12:18:56AM +0100, Gregory Stark wrote:
> 
> Not all countries break up their national tld space into sections like .co.uk
> or .com.au. Canadian domains can be bought directly under .ca like amazon.ca.
> 
> I think you'll have to store a specific list of tlds and how deep you want to
> look.

Another way to look at this is that any containing domain is just a
domain.  So .info is a domain, example.info is a domain, and in case
of the existence of host1.some.example.info, some.example.info is a
domain.  Also, co.uk is just as much a domain as yahoo.co.uk.  

Some poor misguided people at Netscape badly misunderstood the DNS
many years ago, and web browser cookies have been attempting to
recover from that misunderstanding ever since (with sometimes serious
security implications).  There's really no reliable way to deduce
common responsibility from the DNS labels, and it's sometimes
terrifically important not to make that mistake.

A

-- 
Andrew Sullivan  | ajs@crankycanuck.ca
The plural of anecdote is not data.
		--Roger Brinner