Re: [PATCHES] ALTER SCHEMA ... SET TABLESPACE

Fabien COELHO wrote:
>
> > Fortunately, I think the change schema default tablespace is unusual
> > enough that we can wait for 8.1 where people will really want the
> > ability to move schemas for already-created objects too.
>
> Ok. I disagree;-) Or one has to consider that tablespace is just
> "experimental" and should not be used but for simple tests. If so, maybe a
> warning should be output everytime the feature is used...
>
> ISTM that most people don't need tablespace at all. So it is ok for them.
>
> However, those who might consider using tablespace because they need it
> will have somehow a lot of data. Their large amount of data is likely to
> be precious to them. If they are messed up because they cannot move them
> around as they need it, they won't be happy. Saying things like "you can
> just pg_dump/pg_restore" or "edit pg_dump output by hand" won't make them
> very happy either, esp if the amount of data is huge, and it may well be
> the case if they use tablespace.
>
> It seems to me that the current implementation is not completed. For
> instance, do you expect someone to be able to remove a tablespace? At the
> time it is not always possible, because all objects cannot be moved away
> from a tablespace (namely sequence, as it is considered useless to move
> them, what looks true from a performance perspective, but not from an
> administrator perspective).
>
> So it seems to me that tablespace handling must be looked at very
> carefully from a "big data" user perspective and their need.
>
> Well, as usual, I may be quite wrong;-)

You make a strong argument. All we can tell people is that we did the
best we could given our constraints and that it will be improved in 8.1.
We already have TODO entries for all tablespace limitations and
fortunately most people read that file so hopefully people will prefer
what we gave them rather than nothing. They aren't required to use them
if the limitations are not acceptable. We could mention the limitations
in the release notes if people want that.

--
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