1. Efficient SPARQL-to-SQL translation using R2RML Mappings
KRDB Research Centre
for Knowledge and Data

2. Agenda SPARQL-to-SQL Integrating R2RML Optimization Benchmark
SPARQL-to-Datalog
Datalog-to-SQL
Integrating R2RML
Optimization
Benchmark

3. Overview Flow of approach Datalog representation
Efficiently manipulation and optimization
Combination with R2RML
Formal ground to ensure correctness

4. SPARQL-to-SQL SPARQL to Datalog Translation rules
Axel Polleres. From SPARQL to rules (and back). In Proc. of the 16th Int. World Wide Web Conf. (WWW 2007), pages 787–796. ACM, 2007.
Translation rules

5. SPARQL-to-SQL Example
ans is the root and the triple atoms are the leaves.

6. SPARQL-to-SQL
Datalog to SQL
Example

7. Integrating R2RML mappings
R2RML mapping node

8. Integrating R2RML mappings
Triple map node translation
Example

9. Optimisation Program flattening Semantic Query Optimisation(SQO)
Primary and Foreign keys
r1 : ans1(x,y) :-
triple( x
,“rdf:type”,“:Student”),
triple(x,“:name”,y)
r2 :
triple(
concat(“:stud/”,id)
,“rdf:type”,“:Student”)
:- student(id,name)
ans1(concat(“:stud/”,id1),y) :- student(id1,name1),
triple(concat(“:stud/”,id1),“:name”,y)

10. Benchmark Benchmark frameworks BSBM: 25 queries
FishMark: 22queries, queries are larger

11. Thank you!