Semmle Limited

Mathieu Verbaere

Oege De Moor

Elnar Hajiyev

Max Schaefer

Pavel Avgustinov

Damien Sereni

A novel system, computer readable storage medium and method for creating re-usable queries over complex data including hierarchies, trees and graphs is described. This is achieved by an object-oriented query language, where a class is a logical property of a data item, and inheritance is implication between such properties. Virtual method calls execute all relevant method implementations in most specific classes. Expressions can be multi-valued, thus avoiding the need for naming intermediate results. All constructs closely follow the syntax of mainstream object-oriented languages like Java.

Querying an object-oriented data hierarchy using relational query languages

Creating concise and re-useable queries over complex data

A method and system is provided for computing an approximation of the results of a query. The approximation represents a superset of all possible results, by computing a set of records of types (as opposed to a set of records of values, which is the normal result of a query). This is different from conventional systems, which typically infer types for each field individually. For each record of types, one may also keep track of equalities of fields to improve the precision of the approximation. The approximation can be used to detect erroneous parts of queries that always return an empty result, regardless of the contents of the data source. Furthermore, the same approximation is also useful in performing optimizations: first, by eliminating parts of procedure calls that are guaranteed to be irrelevant to the calling context, and second, by eliminating unnecessary type tests in the query.

Approximating query results by relations over types for error detection and optimization

A system, computer readable storage medium and method for creating re-usable queries over complex data including hierarchies, trees and graphs is described. This is achieved by an object-oriented query language, where a class is a logical property of a data item, and inheritance is implication between such properties. Virtual method calls execute all relevant method implementations in most specific classes. Expressions can be multi-valued, thus avoiding the need for naming intermediate results. All constructs closely follow the syntax of mainstream object-oriented languages like Java.

Growing community of inventors

Oxford, United Kingdom

Mathieu Verbaere