Bug in -c CLI option of pg_dump/pg_restore

Guillaume Lelarge <guillaume@lelarge.info>

From: Guillaume Lelarge <guillaume@lelarge.info>
To: pgsql-hackers <pgsql-hackers@postgresql.org>
Cc: "Jehan-Guillaume (ioguix) de Rorthais" <jgdr@dalibo.com>, Gilles Darold <gilles.darold@dalibo.com>
Date: 2012-10-13T14:47:06Z
Lists: pgsql-hackers

Attachments

Hi,

One of my colleagues, Jehan-Guillaume de Rorthais, found a weird
behaviour of the "-c" command line option in the pg_restore tool while
doing a training. Here is the following steps he followed:

createdb foo
<adds a few objets in foo>
pg_dump -Fc foo > foo.dump
createdb bar
pg_restore -c -d bar foo.dump

bar contains the same objects as foo (nothing unusual here), but... foo
is no longer present. Actually, if you use the "-c" command line option,
you get a "DROP DATABASE" statement. To me, it feels like a quite
terrible bug.

It's quite easy to reproduce. Just create a database, and use pg_dump
with the "-c" option:

createdb foo
pg_dump -s -c foo | grep DATABASE

and you end up with this:

DROP DATABASE foo;

I tried from 8.3 till 9.2, and only 9.2 has this behaviour.

You'll find attached a patch that fixes this issue. Another colleague,
Gilles Darold, tried it in every possible way, and it works. I'm not
sure the test I added makes it a very good patch, but it fixes the bug.

Regards.


-- 
Guillaume
http://blog.guillaume.lelarge.info
http://www.dalibo.com

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