Re: Performance of UPDATE operation

On Mon, Feb 13, 2023 at 10:09 AM Mkrtchyan, Tigran <tigran.mkrtchyan@desy.de>
wrote:

>
>          0.524           0  BEGIN;
>          0.819           0  INSERT INTO t_inodes (inumber, icrtime,
> igeneration)
>          0.962           0  UPDATE t_inodes SET igeneration = igeneration
> + 1 where  inumber = :inumber;
>          9.203           0  END;
> ```
>
> My naive expectation will be that updating the newly inserted record
> should cost nothing


It takes less than 1/10 of the total time.  That is pretty close to
nothing.  Why would you expect it to be truly free?


> ... Are there ways
> to make it less expensive?
>

Obviously here you could just insert the correct value in the first place
and not do the update at all.

Cheers,

Jeff