From: Tom Lane <tgl@sss.pgh.pa.us>
To: "David G. Johnston" <david.g.johnston@gmail.com>
cc: =?UTF-8?Q?gmail_Vladimir_Kokovi=C4=87?= <vladimir.kokovic@gmail.com>,
        pgsql-novice <pgsql-novice@postgresql.org>,
        Ken Benson <Ken@infowerks.com>
Subject: Re: chr(3) and 3::text
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Comments: In-reply-to "David G. Johnston" <david.g.johnston@gmail.com>
	message dated "Sat, 28 Mar 2020 08:25:52 -0700"
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Date: Sat, 28 Mar 2020 12:02:26 -0400
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"David G. Johnston" <david.g.johnston@gmail.com> writes:
> On Sat, Mar 28, 2020 at 8:09 AM gmail Vladimir Koković <
> vladimir.kokovic@gmail.com> wrote:
>> Main question is, why is 3::text == '3' ?

> Its that way because :: is defined to make it that way.

More concretely: for most types, casting to text is defined to produce the
textual representation of the value.  An unadorned literal 3 starts life
as type integer, so what you've got here is an integer-to-text cast,
and that's going to convert the integer the same way it would be output.

			regards, tom lane