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From: Don Y <blockedofcourse@foo.invalid>
Newsgroups: sci.electronics.design
Subject: Re: Serial, concurrent, parallel
Date: Fri, 17 Jan 2025 13:59:26 -0700
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On 1/17/2025 1:50 PM, Don Y wrote:
> It will also ensure that multistep operations all happen
> as an indivisible (atomic) "transaction" so no other
> user (accessing the database at that same instant)
> will ever see "partial results".  E.g., adjusting the
> population of locality 5 down by 321 souls to reflect the
> folks who have RELOCATED to locality 88 (you will never
> see 321 *extra* people nor 88 *fewer* people, depending

s/88/321/

> on the order in which the *individual* population counts
> were "adjusted".)

I.e., I can:
    adjust the population of locality 5 down by 321
    THEN, adjust the poulation of locality 88 *up* by 321
OR
    adjust the population of locality 88 up by 321
    THEN, adjust the population of locality 5 down by 321

If <someone> peeks at this data between the first "step"
and the second, they will either see 321 fewer people
living in the country (!) or 321 *more* -- when the
total population hasn't actually changed (as is evident
before and after the "transaction")