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Date: Wed, 10 Sep 2025 08:15:35 -0700
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Subject: Re: MVCC and all that...
To: Ron Johnson <ronljohnsonjr@gmail.com>,
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From: Adrian Klaver <adrian.klaver@aklaver.com>
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On 9/10/25 08:11, Ron Johnson wrote:
> On Wed, Sep 10, 2025 at 11:08 AM Ellen Allhatatlan 
> <ellenallhatatlan@gmail.com <mailto:ellenallhatatlan@gmail.com>> wrote:
> [snip]
> 
>     So, you have table X - it has 2M rows (say, 0.5 GB) in the first file
>     (along with all the other tables). The 2GB limit is hit, more data is
>     added. 0.7 GB is added to table X - these records go into a new
>     database file - the table is split in two - you have 2 "extents" of
>     2GB with X split 0.5 - in extent1, 0.7 in extent2. All mixed up with
>     other tables as well!
> 
>     That was the architectural flaw to which I was referring. Nothing to
>     do with PG
> 
> You're gonna be in for a very rude surprise after adding 1GB of data to 
> a PG table...

Yes, but the table is split not the database as a whole per:

https://www.postgresql.org/docs/current/storage-file-layout.html

> 
> -- 
> Death to <Redacted>, and butter sauce.
> Don't boil me, I'm still alive.
> <Redacted> lobster!


-- 
Adrian Klaver
adrian.klaver@aklaver.com