From: Andreas Kretschmer <akretschmer@spamfence.net>
To: pgsql-sql@postgresql.org
Subject: Re: conditional FROM
Date: Sat, 10 Dec 2011 17:17:25 +0100
Message-ID: <20111210161725.GA15506@tux> (raw)
In-Reply-To: <20111210170332479879.3df30525@klingler.net>
References: <20111210170332479879.3df30525@klingler.net>
Richard Klingler <richard@klingler.net> wrote:
> Good day...
>
> I'm trying to build a query for PGSQL 9.1 where a table has two
> references with only one being used depending of the type of entry..
>
> For example, the table has following simplified structure:
>
> portid primary key
> port2node index to table node
> port2card index to table card
>
> So how can I do a conditional FROM clause in the query depending on the
> column port2node and port2card?
> If port2card is Null or 0 I don't want it in the FROM clause as the
> query will return unneccessary duplicate
> row...the same goes for port2node being Null or 0...
I think, you can't do that, you have to build your query and execute
that string. You should use a function to do that.
Andreas
--
Really, I'm not out to destroy Microsoft. That will just be a completely
unintentional side effect. (Linus Torvalds)
"If I was god, I would recompile penguin with --enable-fly." (unknown)
Kaufbach, Saxony, Germany, Europe. N 51.05082°, E 13.56889°
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To: pgsql-sql@postgresql.org
Cc: akretschmer@spamfence.net
Subject: Re: conditional FROM
In-Reply-To: <20111210161725.GA15506@tux>
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