Re: Universal B-tree

For research purpose, I think that expression index is a good idea. I just
want to do a proof of concept.

The other issue is that my algorithm break a z-order interval into several
intervals that represents the query box. How should I create it without
creating any overhead?

Best regards,

daniel

2010/8/9 Greg Stark <gsstark(at)mit(dot)edu>

> On Mon, Aug 9, 2010 at 5:31 PM, Daniel Oliveira
> <danielmarquesoliveira(at)gmail(dot)com> wrote:
> > I don't need to change B-tree estructure. I just need integrate my encode
> > function that transforms multiple keys into one key by bit-interleaving
> and
> > to acess elements given several intervals (range search).
>
> You could build a "expression" index on the function which will build
> a regular btree. Then any range clause on a similar expression in the
> query would be able to use the index. Postgres is capable of detecting
> multiple range clauses that can use one or more indexes and combine
> the results. It might not be perfect for your use case, being a
> general purpose tool.
>
> I'm not sure how feasible it would be to implement a special purpose
> case that matches your needs. Perhaps a special index type and index
> access method similar to gist "tsquery" data type. But that's a lot
> more work and a lot more C coding.
>
> --
> greg
>