REGAL⁺: Reverse engineering SPJA queries

The goal of query reverse engineering is to re-generate the SQL query that produced a given result from some known database. The problem has many real world applications where users need to better understand the lineage and trust- worthiness of various data reports even when the authors of those reports are no longer reachable or are unable to provide the required explanations anymore. It gets more challenging as the complexities of both the query and database schema increase. Prior work has addressed the reverse engineering of constrained types of SQL queries and sometimes on constrained schemas, such as single-table schemas. In this demonstration, we present a framework called REGAL⁺, which builds upon, and extends prior work to enable the discovery of Select-Project-Join-Aggregation (SPJA) queries over arbitrary schemas. Without any prior schema knowledge or SQL expertise, the user only needs to upload a data report (e.g., as a spreadsheet), and the system will automatically compute and display the queries capable of generating that report from the database.