Re: finding firstname + lastname groups

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От Scott Marlowe
Тема Re: finding firstname + lastname groups
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Msg-id dcc563d10806191339p757a4ffdp2d851d06d01561a4@mail.gmail.com
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Ответ на finding firstname + lastname groups  ("blackwater dev" <blackwaterdev@gmail.com>)
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On Thu, Jun 19, 2008 at 1:38 PM, blackwater dev <blackwaterdev@gmail.com> wrote:
> I have to find the same firstname+ lastname combo in my db and see which
> name appears the most so I basically need to do the following:
>
> select name, count(name) from people group by name having count(name)>1
>
> The problem is name is not one column but made up of firstname,
> lastname...how do I do this?

You can concatenate them.  Just use a unique separator like a : symbol
or something.   You can do it with a subselect if you like, or in a
single level query.

select last||':'||first, count(last||':'||first) from people group by
last||':'||first having count(last||':'||first) > 1

OR subselect style:

select a.wholename, count(a.wholename) from
    (select last||':'||first as wholename from people) as a
group by a.wholename having count(a.wholename) > 1

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