3 papers
cs.LO2021
On Doctrines and Cartesian Bicategories
Filippo Bonchi, Alessio Santamaria, Jens Seeber +1
We study the relationship between cartesian bicategories and a specialisation of Lawvere's hyperdoctrines, namely elementary existential doctrines. Both provide different ways of a…
cs.LO2020
Cartesian bicategories with choice
Filippo Bonchi, Jens Seeber, Pawel Sobocinski
Relational structures are emerging as ubiquitous mathematical machinery in the semantics of open systems of various kinds. Cartesian bicategories are a well-known categorical algeb…
cs.LO2018
Graphical Conjunctive Queries
Filippo Bonchi, Jens Seeber, Pawel Sobocinski
The Calculus of Conjunctive Queries (CCQ) has foundational status in database theory. A celebrated theorem of Chandra and Merlin states that CCQ query inclusion is decidable. Its p…