Re: pgsql: Add template for adaptive radix tree

On Thu, Mar 7, 2024 at 1:32 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
> John Naylor <johncnaylorls(at)gmail(dot)com> writes:
> > On Thu, Mar 7, 2024 at 1:08 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >> Hm ... do we know that this is not patent-encumbered technology?
> >> Commits citing such specific prior art make me nervous.
>
> > There are several open source implementations in a variety of
> > languages, so I assumed not.
>
> Are any of those implementations used in places that might
> entice a patent troll to come after them?
>
> (If you think Postgres isn't an inviting target for patent
> trolls, you're wrong. We've avoided getting sued so far,
> but man this topic scares me.)

Understandably so. FWIW, the use case proposed by the authors was for
secondary indexes within in-memory databases, not as a type of
associative array. I'm unable to find patents for the thing itself,
but IANAL. I believe I've been in contact with some of the same
authors about a different subject, and they seemed open to people
trying to implement their ideas (it was a different paper, to be sure,
and unfortunately I no longer email account).