Re: SQL question.... - Mailing list pgsql-sql

Gurjeet Singh wrote:

On Wed, May 21, 2008 at 4:47 AM, Karl Denninger <karl@denninger.net> wrote:

Gurjeet Singh wrote:

On Tue, May 20, 2008 at 11:44 PM, Karl Denninger <karl@denninger.net <mailto:karl@denninger.net>> wrote:

   .... assuming the following schema:

   create table access (name text, address ip)

   I want to construct a SELECT statement which will return ONLY
   tuples containing IP and name pairs IF there is an IP that has two
   or more NAMEs associated with it.

   I've not figured out how to do this; I can get a list of all IPs
   and names ordered by IP, which I could then parse with a different
   program (e.g. "Select name, address from access order by
   address"), but the idea of course is to do it with one SELECT
   statement and return only rows that have multiple names listed for
   a given IP.


try this:

select ip, name from access where ip in ( select ip from access group by ip having count(name) > 2);

heven't execued it, so may need some coaxing. Let me know the results.

Best regards,
--

A small modification got CLOSE.... I can live with that set of results..... I think.

I am glad.

Harold had posted almost identical solution one hour before I did (I had the mail ready to be sent almost after you posted, but lost power and network connection for about an hour).

Can you please post your modified query, for the record; we might still be able to get you _exactly_ what you want.

Best regards,

I used an "order by" and also increased the count to "> 2" because there are a lot of blank "name" records in there as well (but I don't want to select on those; as an artifact of how the system works there will usually be a blank name entry for most IP corresponding entries, but not all)