Scheme Request for Implementation 168,
"Generic Tuple Store Database,"
by Amirouche Boubekki,
has gone into "final" status.
The document and an archive of the discussion are available at https://srfi.schemers.org/srfi-168/.
Here's the abstract:
This library is a generic approach to the database abstractions known as triplestore and quadstore. Generic Tuple Store Database implements n-tuple ordered sets and associated primitives for working with them in the context of data management.
Many thanks to Amirouche and to everyone who contributed to the discussion of this SRFI.