Re: .backup files not needed?

Simon Riggs wrote:
> Just had questions from a replication user about why the .backup file is
> described as "can ordinarily be ignored" and is considered optional by
> recovery also even when pg_start_backup() was used.
>
> If the file was created, it is necessary to use it in recovery, so
> should never be ignored as the docs imply.
>
> Can we remove the phrase ", and can ordinarily be ignored." ? from
> doc/src/sgml/backup.sgml
>
>   <para>
>     To make use of the backup, you will need to keep around all the WAL
>     segment files generated during and after the file system backup.
>     To aid you in doing this, the <function>pg_stop_backup</> function
>     creates a <firstterm>backup history file</> that is immediately
>     stored into the WAL archive area. This file is named after the first
>     WAL segment file that you need to have to make use of the backup.
>     For example, if the starting WAL file is
>     <literal>0000000100001234000055CD</> the backup history file will be
>     named something like
>     <literal>0000000100001234000055CD.007C9330.backup</>. (The second
>     part of the file name stands for an exact position within the WAL
>     file, and can ordinarily be ignored.) Once you have safely archived
>     the file system backup and the WAL segment files used during the
>     backup (as specified in the backup history file), all archived WAL
>     segments with names numerically less are no longer needed to recover
>     the file system backup and can be deleted. However, you should
>     consider keeping several backup sets to be absolutely certain that
>     you can recover your data.
>    </para>

The comment is saying "the second part of the file name" can be ignored,
not the backup file itself.

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + If your life is a hard drive, Christ can be your backup. +