Re: tweaking NTUP_PER_BUCKET

Hi,

Thinking about this a bit more, do we really need to build the hash
table on the first pass? Why not to do this:

(1) batching   - read the tuples, stuff them into a simple list   - don't build the hash table yet

(2) building the hash table   - we have all the tuples in a simple list, batching is done   - we know exact row count,
cansize the table properly   - build the table
 

Also, maybe we could use a regular linear hash table [1], instead of
using the current implementation with NTUP_PER_BUCKET=1. (Although,
that'd be absolutely awful with duplicates.)

regards
Tomas

[1] http://en.wikipedia.org/wiki/Linear_probing