Re: postmaster.pid

> > i think that somewhere in the docs the administators
> > should be advised to delete postmaster.pid automatically at boot
> > time ( for example at the same time when the files in /tmp are
> > deleted ).
> > This way, in case of an unexpected shutdown, postgresql would be
> > able to restart without any manual intervention.

> Well, this is a *BAD IDEA*. Suppose, for example, your data is corrupt in
> some special way, an due to your removal of the pid file, postmaster tries to
> recover the database automatically and probably destroys all or data part of
> the data. You would like to have been able to do a filseystem level backup
> first...

Ooopss...  it seems like i am too optimistic about such situations.

Just wondering: if the database is so heavily damaged that the
postmaster would not be able to recover,  are there any chances to
restore anything from a filesystem backup, manually ?

.........

Background:
  - our team is working on a project for a small company.
  - there will be one server and 3-4 clients
  - It is the first time we use PostgreSQL.
  - Little space.
  - Many people around.
  - No UPS (yet).
  - unpredictable,untrained,desperate,'crazy' users

Possible problems:
  - the users will need time to learn how to use the program
    ( until then they could do many mistakes, such as turning off the
      server before leaving the office - without issueing the proper
      shutdown command, but simply pushing the power switch. )
  - someone might stumble over the cable and unplug the server by mistake.

Questions:
  How resistent is PostgreSQL to such shocks?

  Are there alternative solutions to handling unexpected shutdowns
  automatically?   (except deleting postmaster.pid at boot time)



Best wishes,

Adrian Maier
(am@fx.ro)