Message-ID: <4EB8AF9C.7060305@comodo.com>
Date: Tue, 08 Nov 2011 09:57:08 +0530
From: Robins Tharakan <robins.tharakan@comodo.com>
Organization: Comodo
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To: pgsql-sql@postgresql.org
CC: Tarlika Elisabeth Schmitz <postgresql6@numerixtechnology.de>
Subject: Re: GROUP and ORDER BY
References: <20111107212031.4d6310aa@dick.coachhouse>
In-Reply-To: <20111107212031.4d6310aa@dick.coachhouse>
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Unless I overlooked something here, does this work ?

SELECT no, name, MAX(similarity(name, 'Tooneyvara')) AS sim
FROM vtown
WHERE similarity(name, 'Tooneyvara') > 0.4
GROUP BY no, name
ORDER BY sim DESC

--
Robins Tharakan

On 11/08/2011 02:50 AM, Tarlika Elisabeth Schmitz wrote:
> Hello,
>
> I would like to GROUP the result by one column and ORDER it by another:
>
> SELECT
>      no, name, similarity(name, 'Tooneyvara') AS s
>      FROM vtown
>      WHERE    similarity(name, 'Tooneyvara')>  0.4
>      ORDER BY s DESC
>
> Result:
>
> 1787	"Toomyvara"	0.5
> 1787	"Toomevara"	0.4
> 1188	"Toonybara"	0.4
>
>
> Desired result:
>
> 1787	"Toomyvara"	0.5
> 1188	"Toonybara"	0.4
>
> Gets rid of the  duplicate "no" keeping the spelling with the greater
> similarity and presents the remaining result ordered by similarity.
>
>
> My solution:
>
> SELECT * FROM
> (
> SELECT DISTINCT ON (no)
>      no, name,
>      similarity(name, 'Tooneyvara') AS sim
>      FROM vtown
>      WHERE similarity(name, 'Tooneyvara')>  0.4
>      ORDER BY no, sim DESC
> ) AS x
> ORDER BY sim
>
>
> Is that the best way to achieve this result?