On Mon, May 11, 2020 at 05:33:40PM -0700, Peter Geoghegan wrote:
> On Mon, May 11, 2020 at 5:14 PM Bruce Momjian <bruce@momjian.us> wrote:
> > Agreed. How is this?
> >
> > This allows efficient btree indexing of low cardinality columns.
> > Users upgrading with pg_upgrade will need to use REINDEX to make use of
> > this feature.
>
> I still think that the release notes should say that the key is only
> stored once, while TIDs that identify table rows are stored together
> as an array. Everything that's helpful (or harmful) about the feature
> happens as a consequence of that. This isn't hard to grasp
> intuitively, and is totally in line with how things like Oracle bitmap
> indexes are presented to ordinary users.
I still don't think these details belong in the release notes.
--
Bruce Momjian <bruce@momjian.us> https://momjian.us
EnterpriseDB https://enterprisedb.com
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