agora inbox for pgsql-sql@postgresql.org
help / color / mirror / Atom feedFrom: Laurenz Albe <laurenz.albe@cybertec.at>
To: Rossi, Maria <maria.rossi@jackson.com>
To: 'pgsql-sql@lists.postgresql.org' <pgsql-sql@lists.postgresql.org>
To: 'pgsql-novice@lists.postgresql.org' <pgsql-novice@lists.postgresql.org>
Subject: Re: pg_dumpall and restore
Date: Tue, 09 Oct 2018 20:28:25 +0200
Message-ID: <47175ca8aea768568fb51e1a91c94d436ef79d97.camel@cybertec.at> (raw)
In-Reply-To: <323742d3468543f590fc081c7fba0c7a@DC03PXMBP003.jacksonnational.com>
References: <323742d3468543f590fc081c7fba0c7a@DC03PXMBP003.jacksonnational.com>
Rossi, Maria wrote:
> I upgraded our postgres database from V9.3 to V10.5. Used pg_dumpall then restore it to the new instance.
> After the restore, we notice that 1 table had duplicate rows, such that it was not able to create the primary key.
> I checked the old database, it does not have the dups.
> Has anyone encountered having dups rows loaded? Any idea what caused this and how to prevent?
>
> Your help would be much appreciated.
I don't believe that pg_dumpall miraculously duplicated the row.
You probably *do* have a duplicate row, and hence table corruption,
but I suspect that one of the rows is not in the index you used
to look for the row.
If you query:
SELECT * FROM tab WHERE id = 42;
the query will likely use the index on "id" and find only one of
the rows.
You should
SET enable_indexscan = off;
SET enable_indexonlyscan = off;
and then repeat the query, so that a sequential scan is used.
To fix, delete one of the rows and reindex.
You can identify a row by its tuple id:
SELECT ctid, * FROM tab WHERE id = 42;
Yours,
Laurenz Albe
--
Cybertec | https://www.cybertec-postgresql.com
view thread (8+ messages) latest in thread
Message-ID: <47175ca8aea768568fb51e1a91c94d436ef79d97.camel@cybertec.at>
Permalink: ../47175ca8aea768568fb51e1a91c94d436ef79d97.camel@cybertec.at/
Also on: postgresql.org/message-id/47175ca8aea768568fb51e1a91c94d436ef79d97.camel@cybertec.at
reply
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-sql@postgresql.org
Cc: laurenz.albe@cybertec.at, maria.rossi@jackson.com, pgsql-sql@lists.postgresql.org, pgsql-novice@lists.postgresql.org
Subject: Re: pg_dumpall and restore
In-Reply-To: <47175ca8aea768568fb51e1a91c94d436ef79d97.camel@cybertec.at>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by agora; see mirroring instructions
for how to clone and mirror all data and code used for this inbox