A Decidable Case of Query Determinacy: Project-Select Views

TL;DR

This paper establishes that query determinacy is decidable for a specific class of views and queries, namely project-select views and certain join queries, under conditions related to the decidability of the underlying selection predicates.

Contribution

It identifies a decidable case of query determinacy for project-select views and join queries without self joins, expanding understanding of query determinacy boundaries.

Findings

Decidability of query determinacy for project-select views.

Decidability depends on the underlying selection predicates' theory.

Applicable to queries with no self joins under certain conditions.

Abstract

Query determinacy is decidable for project-select views and a project-select-join query with no self joins, as long as the selection predicates are in a first-order theory for which satisfiability is decidable.