Institutions for SQL Database Schemas and Datasets

摘要

Databases and the query language SQL play a major role in modern applications. In this paper we present an institution-based formalisation of relational databases that uses structures close to those used in SQL. This is the essential difference to other category-theoretical formalisations of databases, which often depart quite far from the SQL standard. We also study SQL queries, using institutional monads, and prove cocompleteness and amalgamation results for the institution.