Re: WIP: Covering + unique indexes.

On Sun, Apr 8, 2018 at 11:19 PM, Teodor Sigaev <teodor(at)sigaev(dot)ru> wrote:
> Thank you, pushed.

I noticed a few more issues following another pass-through of the patch:

* There is no pfree() within _bt_buildadd() for truncated tuples, even
though that's a context where it's clearly not okay.

* It might be a good idea to also pfree() the truncated tuple for most
other _bt_buildadd() callers. Even though it's arguably okay in other
cases, it seems worth being consistent about it (consistent with old
nbtree code).

* There should probably be some documentation around why it's okay
that we call index_truncate_tuple() with an exclusive buffer lock held
(during a page split). For example, there should probably be a comment
on the VARATT_IS_EXTERNAL() situation.

* Not sure that all calls to BTreeInnerTupleGetDownLink() are limited
to inner tuples, which might be worth doing something about (perhaps
just renaming the macro).

I do not have the time to write a patch right away, but I should be
able to post one in a few days. I want to avoid sending several small
patches.

--
Peter Geoghegan