Martijn van Oosterhout <kleptog(at)svana(dot)org> writes:
> What syntax were you envisioning? Does this value just need to be
> passed to GiST at the creation of the the index, or does it actually
> need to remembered by the backend and passed each call?
I should think that the index ought to remember any such info for itself
(eg, in the metapage). Putting it somewhere else, such as the pg_index
row for the index, would force a one-size-fits-all approach.
regards, tom lane