Re: WIP: BRIN multi-range indexes

Hi Tomas, 

I took another look through the Bloom opclass portion (0004) with sorted_mode omitted, and it looks good to me code-wise. I think this part is close to commit-ready. I also did one more proofreading pass for minor details.

+     rows per block). The default values is <literal>-0.1</literal>, and

+     greater than 0.0 and smaller than 1.0. The default values is 0.01,

s/values/value/

+ * bloom filter, we can easily and cheaply test wheter it contains values

s/wheter/whether/

+ * XXX We assume the bloom filters have the same parameters fow now. In the

s/fow/for/

+ * or null if it does not exists.

s/exists/exist/

+ * We do expect the bloom filter to eventually switch to hashing mode,
+ * and it's bound to be almost perfectly random, so not compressible.

Leftover from when it started out in sorted mode.

+ if ((m/8) > BLCKSZ)

It seems we need something more safe, to account for page header and tuple header at least. As the comment before says, the filter will eventually not be compressible. I remember we can't be exact here, with the possibility of multiple columns, but we can leave a little slack space.