Re: deductive databases

alex goldman wrote:
>
> The difference between having functors and not having them is fundamental.
> In one case inference is decidable, and in another it isn't (If you think
> this is uninteresting, you are probably in the wrong business) The
> expressiveness varies accordingly.

Sure. I never said that functors per se were uninteresting in the context of databases, just that if your question is interpreted in a naive way the answer is evidently "no" in a very uninteresting way. Having said that, it still looks a bit artificial if you introduce them only for the reason of boosting the expressive power of the query language.

• Jan Hidders