WP6: Query Transformation WP6 Team Presented by: Diego Calvanese - PowerPoint PPT Presentation

WP6: Query Transformation WP6 Team Presented by: Diego Calvanese Free University of Bozen-Bolzano, Italy Free University of Bozen-Bolzano Optique Y3 Review 09/12/2015 – Munich, Germany

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation WP6 in the Optique Architecture Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (1/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation WP6 in the Optique Architecture Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (1/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation Objectives of WP6 Development of techniques for (semi-)automatic configuration and 1 optimization of the query transformation system. Development of techniques for efficient rewriting of end-user queries into 2 efficiently executable datasource queries by exploiting datasource metadata. Techniques for updating and tuning the query transformation system 3 taking into account the ontology, mapping, and datasource metadata and feedback from the execution layer. Implementation of the above techniques into the query transformation 4 subsystem. Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (2/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation Tasks of WP6 Task 6.1 Transformation System Configuration [M2-M24] Lead by FUB, with UniRoma1 and UoA Task 6.2 Runtime Query Rewriting [M2-M36] Lead by FUB, with UniRoma1 and UOXF .BL Task 6.3 Transformation System Tuning [M24-M43] Lead by FUB, with UoA Task 6.4 Transformation Sub-System Implementation and Evaluation [M7-M46] Lead by FUB, heavy interaction with WP2 Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (3/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation WP6 Year 3 Objectives and Progress Main Objectives: Evaluate realistic queries from the Optique use cases. In WP6, we have concentrated mostly on Statoil queries. (Siemens queries are dealt with in WP5). Analyze and optimize for problematic queries We have developed tuning techniques, based on exact mappings and redundant join elimination, that improve the performance of some complex queries by orders of magnitude. Semi-automatic configuration and optimization We have developed tuning techniques to automatically detect exact mappings and forms of implicit keys, by analyzing the mappings, the ontology, and the database instance. Improve coverage of the query catalogue With the introduction of the tuning techniques, we have significantly extended the coverage of the Statoil catalogue to 98% (i.e., +28% ). Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (4/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation Ontop in the Optique Platform Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (5/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation Outline Task 6.1: Transformation System Configuration 1 Task 6.2: Runtime Query Rewriting 2 Task 6.3: Transformation System Tuning 3 Task 6.4: Query Transformation Sub-System Implementation and Evaluation 4 Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (6/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation Task 6.1: Transformation System Configuration The workplan does not foresee additional work on Task 6.1 during Y3. However, we have further refined the results obtained in Y1 and Y2 towards the achievement of the objectives: New datatypes, required by the Statoil use case, are now supported in the mappings and the ontology: xsd:int , xsd:long , . . . Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (7/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation Outline Task 6.1: Transformation System Configuration 1 Task 6.2: Runtime Query Rewriting 2 Task 6.3: Transformation System Tuning 3 Task 6.4: Query Transformation Sub-System Implementation and Evaluation 4 Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (8/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation Task 6.2: Runtime Query Rewriting Integrating cross-linked datasets (in collaboration with Oslo) [Calvanese, Giese, et al., 2015, 14th Int. Semantic Web Conference (ISWC)] Integration of rules in OBDA [Xiao et al., 2014, 8th Int. Conference on Web Reasoning and Rule Systems (RR)] Answering and rewriting for nested regular path queries [Bienvenu et al., 2014, 14th Int. Conference on the Principles of Knowledge Representation and Reasoning (KR)] Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (9/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation Task 6.2: Runtime Query Rewriting Integrating cross-linked datasets (in collaboration with Oslo) [Calvanese, Giese, et al., 2015, 14th Int. Semantic Web Conference (ISWC)] Integration of rules in OBDA [Xiao et al., 2014, 8th Int. Conference on Web Reasoning and Rule Systems (RR)] Answering and rewriting for nested regular path queries [Bienvenu et al., 2014, 14th Int. Conference on the Principles of Knowledge Representation and Reasoning (KR)] Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (9/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation Data integration Deals with the problem of integrated access to multiple data sources . Key problem: Information about a real-world entity can be distributed over several data sources. Execute queries over multiple data sources, performing distributed joins, 1 and collecting the results. In Optique, this functionality is provided by Exareme, provided it is supplied with the information about which objects to join. Identify equal entities, i.e., which data records actually represent the same 2 real world entity (entity resolution). Example: Wellbore-431170 in EPDS ≈ NPDWellbore-1/6-5 in NPD We assume that entity resolution has already been performed. An issue is how to represent this information so that it can be processed efficiently. Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (10/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation Data integration Deals with the problem of integrated access to multiple data sources . Key problem: Information about a real-world entity can be distributed over several data sources. Execute queries over multiple data sources, performing distributed joins, 1 and collecting the results. In Optique, this functionality is provided by Exareme, provided it is supplied with the information about which objects to join. Identify equal entities, i.e., which data records actually represent the same 2 real world entity (entity resolution). Example: Wellbore-431170 in EPDS ≈ NPDWellbore-1/6-5 in NPD We assume that entity resolution has already been performed. An issue is how to represent this information so that it can be processed efficiently. Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (10/35)

T6.1 Transformation System Configuration T6.2 Runtime Query Rewriting T6.3 Transformation System Tuning T6.4 Implementation and Evaluation Data integration Deals with the problem of integrated access to multiple data sources . Key problem: Information about a real-world entity can be distributed over several data sources. Execute queries over multiple data sources, performing distributed joins, 1 and collecting the results. In Optique, this functionality is provided by Exareme, provided it is supplied with the information about which objects to join. Identify equal entities, i.e., which data records actually represent the same 2 real world entity (entity resolution). Example: Wellbore-431170 in EPDS ≈ NPDWellbore-1/6-5 in NPD We assume that entity resolution has already been performed. An issue is how to represent this information so that it can be processed efficiently. Diego Calvanese (FUB) WP6: Query Transformation Optique Y3 Review – 09/12/2015 (10/35)