Обсуждение: Extract transaction from WAL
Hello everyone,
I am new to Postgres and I have a query.
I have updated a table which I should not have.
Is there a way to extract the transactions from the WAL and get back the previous data?
Is there a tool that can help to get back the transactions?
Thanks in advance.
Regards,
Jill
On Thu, Nov 21, 2019 at 04:56 Jill Jade <jill779ks@gmail.com> wrote:
Hello everyone,I am new to Postgres and I have a query.I have updated a table which I should not have.Is there a way to extract the transactions from the WAL and get back the previous data?Is there a tool that can help to get back the transactions?
The normal way is to use a backup along with point in time recovery. But this requires you’ve setup backups and are archiving WALs F/ex with pgbackrest. You restore the last full backup from before the incident and play back to a time stamp or transaction ID. Either to the original server or elsewhere...in this case I would probably restore elsewhere and extract the data I needed using tools like pg_dump to restore the selected data.
I’m personally unaware of other methods which may exist.
Thanks in advance.Regards,Jill
"Genius might be described as a supreme capacity for getting its possessors
into trouble of all kinds."
-- Samuel Butler
On Thu, 2019-11-21 at 12:11 +0400, Jill Jade wrote: > I am new to Postgres and I have a query. > > I have updated a table which I should not have. > > Is there a way to extract the transactions from the WAL and get back the previous data? > > Is there a tool that can help to get back the transactions? This information is not contained in the WAL. You'll have to restore a backup. Yours, Laurenz Albe -- Cybertec | https://www.cybertec-postgresql.com
Hi,
funny enough, this pb looks similar to mine.
the point is: how to guess: what is the "data I need" ??
Looks like we are looking for a way to ask postgres: which transactions have occurred between this and that.
Obviously, if we can have, online, both the db after the PITR and the db "corrupted" we can try to create a dblink from one to the other and, then try to extract the "differences".
but this is not always possible. hence the question about wals.
or ?
regards,
On Thu, Nov 21, 2019 at 3:24 PM Michael Loftis <mloftis@wgops.com> wrote:
--On Thu, Nov 21, 2019 at 04:56 Jill Jade <jill779ks@gmail.com> wrote:Hello everyone,I am new to Postgres and I have a query.I have updated a table which I should not have.Is there a way to extract the transactions from the WAL and get back the previous data?Is there a tool that can help to get back the transactions?The normal way is to use a backup along with point in time recovery. But this requires you’ve setup backups and are archiving WALs F/ex with pgbackrest. You restore the last full backup from before the incident and play back to a time stamp or transaction ID. Either to the original server or elsewhere...in this case I would probably restore elsewhere and extract the data I needed using tools like pg_dump to restore the selected data.I’m personally unaware of other methods which may exist.Thanks in advance.Regards,Jill
"Genius might be described as a supreme capacity for getting its possessors
into trouble of all kinds."
-- Samuel Butler