Re: Tablespaces

Greg Stark wrote:
>
> > > I am expecting to hear some bleating about this from people whose
> > > preferred platforms don't support symlinks ;-).  However, if we don't
>
> Well, one option would be to have the low level filesystem storage (md.c?)
> routines implement a kind of symlink themselves. Just a file with a special
> magic number followed by a path.
>
> I'm normally against reimplementing OS services but symlinks are really a very
> simple concept and simple to implement. Especially if you can make a few
> simplifying assumptions: they only ever need to appear as the final path
> element not as parent directories and tablespaces don't need symlinks pointing
> to symlinks. Ideally postgres also doesn't need to implement relative links
> either.

I just checked from the MinGW console and I see:

    # touch a
    # ln -s a b
    # echo test >a
    # cat b
    # l ?
    -rw-r--r--    1 Bruce Mo Administ        5 Mar  2 23:30 a
    -rw-r--r--    1 Bruce Mo Administ        0 Mar  2 23:30 b
    # cat a
    test
    # cat b
    #

It accepts ln -s, but does nothing with it.

For tablespaces on OS's that don't support it, I think we will have to
store the path name in the file and read it via the backend.  Somehow we
should cache those lookups.

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  Bruce Momjian                        |  http://candle.pha.pa.us
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