From: Andreas Joseph Krogh <andreas@visena.com>
To: pgsql-performance@postgresql.org
Subject: Re: Searching GIN-index (FTS) and sort by timestamp-column
Date: Wed, 16 Mar 2016 14:53:04 +0100 (CET)
Message-ID: <VisenaEmail.55.5cac9849d07151e7.1537fb2771f@tc7-visena> (raw)
In-Reply-To: <27201.1458135447@sss.pgh.pa.us>
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På onsdag 16. mars 2016 kl. 14:37:27, skrev Tom Lane <tgl@sss.pgh.pa.us
<mailto:tgl@sss.pgh.pa.us>>:
Andreas Joseph Krogh <andreas@visena.com> writes:
> 1. Why isnt' folder_id part of the index-cond?
Because a GIN index is useless for sorting.
> 2. Is there a way to make it use the (same) index to sort by
> received_timestamp?
No.
> 3. Using a GIN-index, is there a way to use the index at all for sorting?
No.
> 4. It doesn't seem like ts_rank uses the index for sorting either.
Same reason.
regards, tom lane
So it's basically impossible to use FTS/GIN with sorting on large datasets?
Are there any plans to improve this situation?
Thanks.
-- Andreas Joseph Krogh
CTO / Partner - Visena AS
Mobile: +47 909 56 963
andreas@visena.com <mailto:andreas@visena.com>
www.visena.com <https://www.visena.com;
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To: pgsql-performance@postgresql.org
Cc: andreas@visena.com
Subject: Re: Searching GIN-index (FTS) and sort by timestamp-column
In-Reply-To: <VisenaEmail.55.5cac9849d07151e7.1537fb2771f@tc7-visena>
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