Re: pg_basebackup vs. Windows and tablespaces

On Fri, Nov 14, 2014 at 1:15 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Generally I'd be in favor of avoiding platform-dependent code where
> possible, but that doesn't represent a YES vote for this particular
> patch.  It looks pretty messy in a quick look, even granting that the
> #ifdef WIN32's would all go away.

Hmm, OK.  I have not read the patch.  Hopefully that's something that
could be fixed.

> A larger question here is about forward/backward compatibility of the
> basebackup files.  Changing the representation of symlinks like this
> would break that.  Maybe we don't care, not sure (is there already a
> catversion check for these things?).  Changing the file format for only
> some platforms seems like definitely a bad idea though.

What are the practical consequences of changing the file format?  I
think that an old backup containing symlinks could be made to work on
a new server that knows how to create them, and we should probably
design it that way, but a physical backup isn't compatible across
major versions anyway, so it doesn't have the same kinds of
repercussions as changing something like the pg_dump file format.

-- 
Robert Haas
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