From: Ron <ronljohnsonjr@gmail.com>
To: pgsql-admin@lists.postgresql.org
Subject: Re: delete then insert
Date: Fri, 17 Jan 2020 14:12:10 -0600
Message-ID: <4e1f53ad-6793-c714-46bc-bc7d16b836b1@gmail.com> (raw)
In-Reply-To: <BN6PR19MB00810F01715E27D5AE8D77D0A3310@BN6PR19MB0081.namprd19.prod.outlook.com>
References: <BN6PR19MB00810F01715E27D5AE8D77D0A3310@BN6PR19MB0081.namprd19.prod.outlook.com>
On 1/17/20 2:03 PM, Ken Benson wrote:
>
> So – I THINK I know – that when a row is deleted from a table – the row is
> not actually removed from the table – but, merely marked as deleted, thus
> becoming a dead tuple.
> AUTOVACUUM – takes care of the process of removing these dead tuples.
>
> My question. If – an insert occurs to that same table before autovacuum
> comes along, does that inserted record use a dead tuple? Or – does the
> insert result in an actual added row?
>
If there's an open transaction which is still looking at the now-deleted
record, then over-writing that area of the file would be a Bad Thing.
--
Angular momentum makes the world go 'round.
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To: pgsql-admin@postgresql.org
Cc: ronljohnsonjr@gmail.com, pgsql-admin@lists.postgresql.org
Subject: Re: delete then insert
In-Reply-To: <4e1f53ad-6793-c714-46bc-bc7d16b836b1@gmail.com>
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