Message-ID: <b980ef30-29ce-4dec-b5cd-64e961bec3b0@postgresfriends.org>
Date: Wed, 19 Feb 2025 20:02:34 +0100
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Subject: Re: BUG #18594: CASE WHEN ELSE failing to return the expected output
 when the same colum is used in WHEN and ELSE
To: Chris BSomething <xpusostomos@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>
Cc: "David G. Johnston" <david.g.johnston@gmail.com>,
 PostgreSQL Bug List <pgsql-bugs@lists.postgresql.org>
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From: Vik Fearing <vik@postgresfriends.org>
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On 19/02/2025 13:50, Chris BSomething wrote:
>
> On Tue, 18 Feb 2025 at 10:12, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
>     I think such a rule would be pretty dangerous, even if we could
>     implement it easily.  As an example, if you entered something you
>     meant as a timestamp, but you fat-fingered the punctuation or
>     something, it'd likely fall back to being considered just "text",
>
>
> I don't get that, I thought timestamps have to be preceded by "TIMESTAMP".


The SQL standard requires you to do that, but PostgreSQL is a bit more 
lax about it (and in my humble opinion, thankfully so). If you did 
prefix your literals with their type, you wouldn't be having these 
problems in the first place. The problem stems from postgres treating 
your unmarked literal as "unknown" and then trying to figure out what 
the heck it is.

-- 

Vik Fearing