From: Tom Lane <tgl@sss.pgh.pa.us>
To: "=?utf-8?B?6LCt5b+g5rab?=" <zhongtao.tan@seaboxdata.com>
cc: "=?utf-8?B?RGF2aWQgRy4gSm9obnN0b24=?=" <david.g.johnston@gmail.com>,
        "=?utf-8?B?cGdzcWwtYnVncw==?=" <pgsql-bugs@lists.postgresql.org>
Subject: =?UTF-8?Q?Re:_=E5=9B=9E=E5=A4=8D=EF=BC=9ARe:_The_!=3D_and_+/-_sig?=
         =?UTF-8?Q?ns_are_joined_together_as_an_operator?=
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Comments: In-reply-to "=?utf-8?B?6LCt5b+g5rab?=" <zhongtao.tan@seaboxdata.com>
	message dated "Thu, 20 Mar 2025 09:11:33 +0800"
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Date: Wed, 19 Mar 2025 21:44:43 -0400
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"=3D?utf-8?B?6LCt5b+g5rab?=3D" <zhongtao.tan@seaboxdata.com> writes:
> But "!=3D" is not the same as "<>"
> 1!=3D-1,  "!=3D-" as a whole is treated as an operator, not as an operat=
or "!=3D" -1, but in 1<>-1, it is treated as "<>" -1 instead of "<>-" as a=
 whole  is treated as an operator
> I think "!=3D" and "<>" should be treated in the same way

[ shrug... ]  It's not going to happen.  The PG project's position,
as stated in the docs I pointed you to, is that you should write a
space between adjacent operators.  The SQL spec thinks differently,
so we've made sure that you can leave out space between operators
that are defined in the SQL standard, but that's as far as we'll go.
There are too many existing operators, both within PG core and
elsewhere, that would be broken by changing those rules now.

			regards, tom lane