From: Tom Lane <tgl@sss.pgh.pa.us>
To: 2322370369@qq.com
cc: pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #18857: Abnormal string comparison results
In-reply-to: <18857-a9354c81af5b800d@postgresql.org>
References: <18857-a9354c81af5b800d@postgresql.org>
Comments: In-reply-to PG Bug reporting form <noreply@postgresql.org>
	message dated "Thu, 20 Mar 2025 09:53:32 -0000"
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Date: Thu, 20 Mar 2025 10:46:15 -0400
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PG Bug reporting form <noreply@postgresql.org> writes:
> As shown in the example below, on the ASCII table =E2=80=98?=E2=80=99 is=
 larger than =E2=80=98&=E2=80=99. I
> don't think =E2=80=98t=E2=80=99 should be returned here. In the MySQL da=
tabase it does
> return 0.
> Is there some special consideration here?

Read about collations at

https://www.postgresql.org/docs/current/collation.html

You are probably using a non-C collation.  You could say

postgres=3D# SELECT ('?' <=3D '&*CcCV5' collate "C");
 ?column? =

----------
 f
(1 row)

but more likely you want to switch it at the database level.

			regards, tom lane