Downgrading from Postgresql 7.4 to 7.1

On Mon, Apr 19, 2004 at 16:25:21 -0500,
Matt Adams <matt.adams@mercyships.org> wrote:

Hello:

I have an awkward situation where I must downgrade from 7.4 to 7.1. I
have two databases already in 7.4. I'm largely ignorant concerning
postgresql: am I going to have any severe problems downgrading?

You are probably going to have to process the 7.4 dump file before
it can be used to reload the 7.1 database. This shoudln't be too
bad. You might have some performance problems with queries that work
well in 7.4 and not in 7.1. 7.1 doesn't have schemas, so if you were
making use of those you might have to figure out how to get by without
them. You should probably review the release notes for other added
features since 7.1 that you might be using.

-----Original Message-----
From: Matt Adams [mailto:matt.adams@mercyships.org]
Sent: Monday, April 19, 2004 2:25 PM
To: pgsql-general@postgresql.org
Subject: [GENERAL] Downgrading from Postgresql 7.4 to 7.1

Hello:

I have an awkward situation where I must downgrade from 7.4
to 7.1. I
have two databases already in 7.4. I'm largely ignorant concerning
postgresql: am I going to have any severe problems downgrading?

Just dump and load. It is a very simple procedure. One possibility
would be as follows -->

From 7.4:
pg_dump -c -C -D -f output.sql -h localhost
<your_database_name_goes_here>

Into 7.1:
psql -h localhost -f output.sql template1

If you are using features that are available in 7.4 and not available in
7.1 then you may have problems.

I would think if you simply did a pg_dump and then re-imported it you
shouldn't see any problems.

--Joe

-----Original Message-----
From: Matt Adams [mailto:matt.adams@mercyships.org]
Sent: Monday, April 19, 2004 5:25 PM
To: pgsql-general@postgresql.org
Subject: [GENERAL] Downgrading from Postgresql 7.4 to 7.1

Hello:

I have an awkward situation where I must downgrade from 7.4
to 7.1. I
have two databases already in 7.4. I'm largely ignorant concerning
postgresql: am I going to have any severe problems downgrading?

Thanks

Matt
--
Matt Adams <matt.adams@meryships.org> voice +1 (903) 939-7641
Systems Engineer, Mercy Ships IOC

<http://www.mercyships.org/&gt;

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On Mon, Apr 19, 2004 at 04:25:21PM -0500, Matt Adams wrote:

Hello:

I have an awkward situation where I must downgrade from 7.4 to 7.1. I
have two databases already in 7.4. I'm largely ignorant concerning
postgresql: am I going to have any severe problems downgrading?

Almost certainly you'll need to do some fiddling to make the dump
output from 7.4 acceptable to 7.1. My guess is that you'll need to
write some sed or perl do do it adequately for you. You may be in
better shape if you ask pg_dump to use INSERT statements instead, but
be aware that this will at least triple your restore time.

But I also wonder why you want to downgrade that far. 7.1 has
several _really big_ disadvantages. There are plenty of bugs in
there fixed in later versions. Also, 7.1 has the limitation that
VACUUM always blocks, so maintenance of the database will get a whole
lot more expensive (7.1's VACUUM is equivalent to later VACUUM
FULL). Why do you have to do this?

A

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