From: jdmorgan <jdmorgan@unca.edu>
To: Matheus de Oliveira <matioli.matheus@gmail.com>
Cc: pgsql-admin@postgresql.org
Subject: Re: case statement to cath nulls on joined tables
Date: Fri, 03 Feb 2012 13:34:53 -0500
Message-ID: <4F2C28CD.5010809@gmail.com> (raw)
In-Reply-To: <CAJghg4Kyw9HkjHFGXdS+_xL4jPVNxBLqOhgnhN01JtwK2FHtug@mail.gmail.com>
References: <CA+N3S5q5KZhi6ggjQAO2XPSE5OXvt0eQyO0s63bs-1Sjce0AYQ@mail.gmail.com>
<CAJghg4+Uk2+Dh6smvG2n8-xKGCLGT7Ltx_c-cXP3_Gbm6O0RXQ@mail.gmail.com>
<CAJghg4Kyw9HkjHFGXdS+_xL4jPVNxBLqOhgnhN01JtwK2FHtug@mail.gmail.com>
Thanks Matheus. The coalesce method worked like a champ.
Cheers,
Derek
On 2/3/2012 10:09 AM, Matheus de Oliveira wrote:
> Even better:
>
> SELECT COALESCE(value_of_interest, 'more friendly message')
> value_of_interest
> From poly_table left outer join data_table one poly_table.common_id =
> data_table.common_id
>
> --
> Matheus de Oliveira
>
>
>
>
> On Fri, Feb 3, 2012 at 1:05 PM, Matheus de Oliveira
> <matioli.matheus@gmail.com <mailto:matioli.matheus@gmail.com>> wrote:
>
> Try that:
>
> SELECT address, CASE WHEN value_of_interest IS NULL THEN 'more
> friendly message' ELSE value_of_interest END value_of_interest
>
> From poly_table left outer join data_table one
> poly_table.common_id = data_table.common_id
>
>
> --
> Matheus de Oliveira
>
>
>
>
>
> On Fri, Feb 3, 2012 at 10:45 AM, John Morgan <jdmorgan@unca.edu
> <mailto:jdmorgan@unca.edu>> wrote:
>
> Hello,
>
> I am doing a left outer join between a polygon table and a
> data table.
> Everything
> returns fine from this join as expected. However, there are
> cases where
> there isn?t data for a given polygon and this return as the
> expected null
> in the result set. I would like to utilize something like a
> case statement
> to catch the nulls and return a ?more friendly? message. I
> have tried
> unsuccessfully to use the following logic:
>
> *Select case value_of_interest null then ?more friendly
> message? else
> value_of_interest end*
>
> *From poly_table left outer join data_table one
> poly_table.common_id =
> data_table.common_id*
>
> If someone could let me know where I am going wrong it would
> be greatly
> appreciated.
>
> Cheers,
>
> Derek
>
>
>
--
Derek @ NEMAC
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To: pgsql-admin@postgresql.org
Cc: jdmorgan@unca.edu, matioli.matheus@gmail.com
Subject: Re: case statement to cath nulls on joined tables
In-Reply-To: <4F2C28CD.5010809@gmail.com>
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