Обсуждение: read-only database on CD-ROM?

Is it possible to set up a read-only database on external data carrier
such as CD-ROM or DVD? I couldn't find anything similar in postgres
documentation. I have an old database  which I would like to put on to
CD-ROM and to be able to read it occasionaly. I appreciate any hint if
that would be possible or link to documentation.
Thanks in advance

Dragan Matic

Dragan Matic <mlists@panforma.co.yu> writes:
> Is it possible to set up a read-only database on external data carrier
> such as CD-ROM or DVD?

It's not really supported.  I think you could make it work if you did
VACUUM FREEZE in the database, and then CHECKPOINT, just before burning
it on CD.  You can *not* put a whole $PGDATA directory on CD, as the
xlog and clog have to be writable; but you could put one database
subdirectory there.  (It would be a lot easier to use 8.0 and make the
moved-out tree a tablespace, probably.)

A big caveat is that I'm not sure the CD would work if attached to a
different $PGDATA tree, as for instance after a reinstallation.  It
could definitely not be counted on to work across PG version upgrades.
So all in all the answer is probably "not worth the trouble".

            regards, tom lane

Tom Lane wrote:
> Dragan Matic <mlists@panforma.co.yu> writes:
>
>>Is it possible to set up a read-only database on external data carrier
>>such as CD-ROM or DVD?
>
>
> It's not really supported.  I think you could make it work if you did
> VACUUM FREEZE in the database, and then CHECKPOINT, just before burning
> it on CD.  You can *not* put a whole $PGDATA directory on CD, as the
> xlog and clog have to be writable; but you could put one database
> subdirectory there.  (It would be a lot easier to use 8.0 and make the
> moved-out tree a tablespace, probably.)

What about making xlog and clog sym links?
>
> A big caveat is that I'm not sure the CD would work if attached to a
> different $PGDATA tree, as for instance after a reinstallation.  It
> could definitely not be counted on to work across PG version upgrades.
> So all in all the answer is probably "not worth the trouble".

Oh, come on Tom, sounds like a fun thing to try.... :)

--
Until later, Geoffrey