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From: Bruce Momjian <[email protected]>
To: KES <[email protected]>
Cc: David G. Johnston <[email protected]>
Cc: [email protected] <[email protected]>
Subject: Re: Ambiguous usage of 'any' in explanation
Date: Fri, 12 Oct 2018 11:04:33 -0400
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
References: <[email protected]>
	<[email protected]>
	<CAKFQuwYo-oahQS_8x8ax06Gs_y_P02Hjokso3XCLvpOvZip-bQ@mail.gmail.com>
	<[email protected]>

On Fri, Oct 12, 2018 at 01:42:03PM +0300, KES wrote:
> -   The result is NULL if the comparison does not return true for any row,
> +   The result is NULL if no comparison with a subquery row returns true,
>     and it returns NULL for at least one row.
> -The result of ANY is “true” if the comparison returns true for any subquery
> row. The result is “false” if the comparison returns false for every subquery
> row (including the case where the subquery returns no rows). The result is NULL
> if the comparison does not return true for any row, and it returns NULL for at
> least one row.
>  
> Similary to:
> >The result of ALL is "false" even if *at least one*  row yield false
>  
> +The result of ANY is "true" if at least one row yields true.
> The result of ANY is "false" if all rows yield false
> The result of ANY is NULL if no one row yelds true and at least one row yields
> NULL
> When subquery return no rows the result of ANY is "false"
>  
> sentences are short, easy to spot when and how result is changed

Sorry, but I don't like this wording.  The problem is that the
comparison has two row sets --- the left-hand side, and the right-hand
side.  Each row on the left-hand side is compared with the row set on
the right.  I also don't like people thinking about the result of ANY
since it is really <comparison> ANY that is being used.

-- 
  Bruce Momjian  <[email protected]>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

+ As you are, so once was I.  As I am, so you will be. +
+                      Ancient Roman grave inscription +

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