From: Andreas Karlsson <andreas@proxel.se>
Subject: Re: Indexes on UUID - Fragmentation Issue
To: "pgsql-performance@lists.postgresql.org"
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Date: Mon, 29 Oct 2018 15:52:21 +0100
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On 10/29/2018 02:29 PM, Uday Bhaskar V wrote:> I have
> created C function which can generate a sequential UUID, but I am not 
> sure how best I can use that in postgres.
> 
> I would really like to contribute to Postgres, If I can. Please let me 
> know your thoughts or plans regarding UUID generation.

How is it implemented? I can personally see two ways of generating 
sequential UUID:s. Either you use something like PostgreSQL's sequences 
or you can implement something based on the system time plus some few 
random bits which means they will be mostly sequential.

It could be worth checking on the hackers mailing list if there is any 
interest in this feature, but if it works like a sequence it should also 
probably be a sequence if it is ever going to be accepted into the core.

For your own use I recommend doing like Merlin suggested and write an 
extension. As long as you know a bit of C they are easy to write.

Andreas