From: Tom Lane <tgl@sss.pgh.pa.us>
To: bjdev.gthb@laposte.net
cc: pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #18654: From fuzzystrmatch,
 levenshtein function with costs parameters produce incorrect results
In-reply-to: <18654-c09f568d3ba6dfcd@postgresql.org>
References: <18654-c09f568d3ba6dfcd@postgresql.org>
Comments: In-reply-to PG Bug reporting form <noreply@postgresql.org>
	message dated "Mon, 14 Oct 2024 09:14:50 -0000"
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Date: Mon, 14 Oct 2024 12:01:03 -0400
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PG Bug reporting form <noreply@postgresql.org> writes:
> But if we use this function with parameters other than 1 (the default) the
> result is incorrect

> SELECT levenshtein('horses','shorse',1,1,1) => 2 (correct)

> SELECT levenshtein('horses','shorse',100,10,1) => 101 (INCORRECT)
> The correct result is 6 (all the letter have to be substitute and it's not
> possible to have a lower score with others operations)

Hmm, works for me:

u8=# create extension fuzzystrmatch;
CREATE EXTENSION
u8=# SELECT levenshtein('horses','shorse',1,1,1);
 levenshtein 
-------------
           2
(1 row)

u8=# SELECT levenshtein('horses','shorse',100,10,1);
 levenshtein 
-------------
           6
(1 row)

I confess bafflement about why you're getting wrong answers.
You seem to be using a slightly out of date Postgres, but
none of this code has changed meaningfully since about 2016.
Maybe you hit a compiler bug?  Where did you get this copy
of Postgres from --- or if you built it yourself, what build
options did you use?

			regards, tom lane