From: Massimo Ortensi <mortensi@unimaticaspa.it>
To: Erik Wienhold <ewie@ewie.name>
To: pgsql-admin@lists.postgresql.org
Subject: Re: Problems with unique constraints
Date: Thu, 26 Jan 2023 15:31:46 +0100
Message-ID: <1pL3I2-00D3P1-A2@unimaticaspa.it> (raw)
In-Reply-To: <2137860386.717969.1674736784938@office.mailbox.org>
References: <CAK+uD7heWzrAjdRcSYq-z=crnb5mEs8JgsfGYtrK+vb0yrjeKg@mail.gmail.com>
<b977effa32ce6e3088469871e294bea5d4d513b1.camel@cybertec.at>
<1pKzDp-00CgfG-JH@unimaticaspa.it>
<1968679708.705665.1674730579540@office.mailbox.org>
<1pL0ni-00CnZb-3m@unimaticaspa.it>
<2137860386.717969.1674736784938@office.mailbox.org>
Confirmed, the local is the same but sorting changed.
Thanks
Il 26/01/2023 13:39, Erik Wienhold ha scritto:
>> On 26/01/2023 12:52 CET Massimo Ortensi <mortensi@unimaticaspa.it> wrote:
>>
>> we had OS upgrades, but with the same locale.
> Which OS? Locale may still be the same but collation information may have
> changed, resulting in a different sort order.
>
> https://postgresql.verite.pro/blog/2018/08/27/glibc-upgrade.html
>
> Has libc version changed with the OS upgrades?
>
>> Is there any chance to avoid rebuilding of all indexes/constraints by checking
>> the correctness of indexes ?
> Extension amcheck (functions bt_index_check and bt_index_parent_check) can
> verify that btree entries for text are in lexical order.
>
> https://www.postgresql.org/docs/current/amcheck.html
>
>> Il 26/01/2023 11:56, Erik Wienhold ha scritto:
>>
>>> On 26/01/2023 11:11 CET Massimo Ortensi <mortensi@unimaticaspa.it> wrote:
>>>
>>> I had troubles with some unique constraints recently.
>>>
>>> They simply didn't work, not seeing some records (select found only 47
>>> records with specific values instead of 65, insert could create
>>> duplicate records).
>>>
>>> The constraint were on multiple columns. Drop constraint and create
>>> constraint fixed the problem.
>>>
>>> This happened on two servers :
>>>
>>> - a version 10 server, where an abnormal poweroff happened 6 months
>>> ago, found 3 tables with the problem throughout last 6 months.
>>>
>>> - a test server, found the problem on 1 table after upgrading version 10
>>> to 14
>>>
>>> Anythng similar happened to anybody ?
>>> How can I find out if similar problems are present ? constraint and
>>> index looked ok and were used
>>>
>> Are the indexes on string types? Changes to the locale data is one cause:
>> https://www.postgresql.org/message-id/328626.1647362495@sss.pgh.pa.us
> --
> Erik
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-admin@postgresql.org
Cc: mortensi@unimaticaspa.it, ewie@ewie.name, pgsql-admin@lists.postgresql.org
Subject: Re: Problems with unique constraints
In-Reply-To: <1pL3I2-00D3P1-A2@unimaticaspa.it>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox