Robert Haas <robertmhaas@gmail.com> writes:
> Since we haven't actually released spgist yet, I'm wondering if it
> should be revised to look more like btree and hash - that is, add a
> 32-bit version number immediately following the magic number. All
> experience hath shown that it is often much more work to add such
> things later.
With the beta already out, I think we have released it, for some
admittedly-small value of "released". I think it's too late to make
non-pg_upgrade-able changes on mere speculation that they might be a
good idea.
In any case, I would've expected we'd end up changing all these page
formats if we go over to your concept of a metapage for everything.
Fixing indexes that already have some kind of metapage will surely be
trivial compared to fixing heaps.
regards, tom lane