Re: On-disk bitmap index patch

Tom Lane wrote:
> Both of these pages say up front that they are considering read-only
> data.

Can I assume read-mostly partitions could use the read-I/O
efficient indexes on update-intensive partitions of the same
table could use b-tree indexes?

All of my larger (90GB+) tables can have partitions that are either
almost read-only (spatial data updated one state/country at
a time, about quarterly) or are totally read-only (previous
months and years historical data).

> So one of the questions that has to be answered (and the
> submitters have been entirely mum about) is exactly how bad is the
> update performance? If it's really awful that's going to constrain
> the use cases quite a lot, whereas merely "a bit slower than btree"
> wouldn't be such a problem.

Once we have easy-to-use partitioning, would it be the case that
many larger tables will have near-read-only partitions that could
use I/O friendlier indexes (GIN? Hash? Bitmap?)? Any examples
of a large data set that can't be partitioned into hot areas and
read-mostly areas?