From: Ragnar Hafstað <gnari@simnet.is>
To: aarni@kymi.com
Cc: pgsql-sql@postgresql.org
Subject: Re: Read count ?
Date: Sat, 26 Feb 2005 13:24:19 +0000
Message-ID: <1109424259.10941.6.camel@localhost.localdomain> (raw)
In-Reply-To: <200502241717.14648.aarni@kymi.com>
References: <200502241717.14648.aarni@kymi.com>
On Thu, 2005-02-24 at 17:17 +0200, Aarni Ruuhimäki wrote:
> Hi,
>
> Could someone please give a hint on how to query the following neatly ?
>
> Get news from a news table that belong to a particular account, get segment
> name from segments table for each news item and read count from read history
> table that gets a news_id and timestamp insert every time the news is read.
> Display everything by news count, most read news first ?
>
> news_id 4, news_header, segment_name x, read 10 times
> news_id 2, news_header, segment_name y, read 8 times
> news_id 1, news_header, segment_name x, read 7 times
> news_id 3, news_header, segment_name x, read 0 times
>
> news_table:
> news_id, account_id, segment_id, news_header, ...
>
> segments_table:
> segment_id, account_id, segment_name
>
> read_history_table:
> history_id, news_id, timestamp
>
how about:
select news_id,news_header,segment_name,count(*)
from news_table
natural join segments_table
natural join read_history_table
where account_id=?
group by news_id,news_header,segment_name;
?
gnari
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To: pgsql-sql@postgresql.org
Cc: gnari@simnet.is, aarni@kymi.com
Subject: Re: Read count ?
In-Reply-To: <1109424259.10941.6.camel@localhost.localdomain>
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