Re: efficient count/join query

On Friday 07 Feb 2003 1:26 pm, Tomasz Myrta wrote:
> Gary Stainburn wrote:
> > On Friday 07 Feb 2003 10:48 am, Tomasz Myrta wrote:
>
> <cut>
>
> > Hi Tomasz,
> >
[snip]
>
> I understood your problem well and I just thought some idea will be enough
> to continue work.
>
> Here is detailed query for your problem:
>
> create view some_view as
> select
> coalesce(hjid,rjid) as jid,
> coalesce(hsid,rsid) as sid,
> coalesce(hcount,1)+count(*)-1 as hcount
> from
> history
> full outer join roster on (hjid=rjid and hsid=rosid)
> group by hjid,rjid,hsid,rosid;
>
> Regards,
> Tomasz Myrta

Many appologoes Tomasz.

Because your select *LOOKED* wrong to me, I didn't even try it. Upon looking
at it again I can see what you're doing. When I tried, it complained about
the counts and grouping, so I moved the count(*) to a sub-select and changed
the coalesce and it's working.

Thanks,

Gary

>
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Gary Stainburn

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