Schema-based data retrieval from knowledge graphs

A computing system comprising:

• memory;
• one or more hardware processors coupled to the memory;
• and
• one or more computer readable storage media storing instructions that, when loaded into the memory, cause the one or more hardware processors to perform operations comprising:
• receiving a request of data records for a data schema;
• obtaining a schema alignment which maps the data schema to a subset of an ontology of a knowledge graph;
• generating one or more queries based on the subset of the ontology of the knowledge graph;
• executing the one or more queries on the knowledge graph;
• composing a list of data records by combining query results returned after executing the one or more queries;
• and
• persisting the list of data records to the data schema,
• wherein a selected query comprises a triple pattern including a class or property defined in the subset of the ontology of the knowledge graph, wherein the schema alignment maps an attribute of the data schema to the class or property,
• wherein the one or more queries are configured to return respective query results corresponding to one or more attributes of the data schema, wherein the schema alignment maps the one or more attributes of the data schema to respective classes or properties defined in the subset of the ontology of the knowledge graph.

One or more non-transitory computer-readable media having encoded thereon computer-executable instructions causing one or more processors to perform a method comprising:

• receiving a request of data records for a data schema;
• obtaining a schema alignment which maps the data schema to a subset of an ontology of a knowledge graph, wherein the schema alignment is obtained from an alignment repository or generated at runtime by a schema matcher;
• generating one or more queries based on the subset of the ontology of the knowledge graph;
• executing the one or more queries on the knowledge graph;
• composing a list of data records by combining query results returned after executing the one or more queries;
• and
• persisting the list of data records to the data schema;
• wherein a selected query comprises a triple pattern including a class or property defined in the subset of the ontology of the knowledge graph, wherein the schema alignment maps an attribute of the data schema to the class or property,
• wherein the one or more queries are configured to return respective query results corresponding to one or more attributes of the data schema, wherein the schema alignment maps the one or more attributes of the data schema to respective classes or properties defined in the subset of the ontology of the knowledge graph.