Re: Dealing with unique IP adresses and ranges

On Tue, 2002-09-03 at 07:21, Mark Fletcher wrote:
> Hello,
>
> No doubt this is a simple question for those more experienced with SQL
> than I (that is, most everyone), but I'm stumped. For the table in
> question, each row represents some information about a particular IP
> address. IP addresses must be unique in regards to a particular user,
> represented by a userId. So far, easy, and the following works for me
> for this:
>
> create unique index ip_index on ip_table( ip, userId );
>
> But what I want is to also be able to store an incomplete IP address,
> representing a range, say a class C block. And when I try to insert a
> row representing a C block, if there are any rows that represent
> complete IP addresses within that C block, it should return an error
> (enforce uniqueness). And vice versa, if there's a row representing a
> class C block, and I try to insert a complete IP address within that
> block, it should return an error.
>
> An example. I insert the following rows:
>
> 1.2.3.1
> 1.2.3.2
> 1.2.3.3
>
> And I try to insert the IP address range 1.2.3, it should error out.
> btw, in my app, IP addresses are represented not as strings, but as
> ints. But if it makes things easier in the database, I can store them as
> strings.
>
> Hope this makes sense. How can I do this?

Have you thought about using the inet or cidr datatypes, rather than
string or int?

You could index on network(ip)

--
Oliver Elphick                                Oliver.Elphick@lfix.co.uk
Isle of Wight, UK
http://www.lfix.co.uk/oliver
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