gql-sql-pgq-pointers

Pointers for GQL and SQL/PGQ

This repository contains pointers to the upcoming GQL (Graph Query Language) standard and the SQL/PGQ extension of the SQL standard. Both allow querying property graphs using the visual graph syntax (a.k.a. ASCII art syntax) popularized by Cypher.

The content of this repository is deployed to https://szarnyasg.github.io/gql-sql-pgq-pointers.

Legend:

• :zap: best for getting started
• :star: probably worth a read
• :dizzy: worth skimming through
• :tv: slides

Standardization

• Property Graph Standards, Process & Timing by Keith Hare
  • 14th LDBC TUC (2021) (:movie_camera: recording)
  • 15th LDBC TUC (2022) (:movie_camera: recording)
  • 16th LDBC TUC (2023) (:movie_camera: recording)
• Pattern matching in GQL and SQL/PGQ (:movie_camera: recording) (2022) by Leonid Libkin
• The Upcoming GQL Standard (2021) by Stefan Plantikow
• Towards GQL 1: Status report on the upcoming ISO/IEC graph query language standard (:movie_camera: recording) (2021) by Stefan Plantikow
• An overview of GQL (:movie_camera: recording) (2022) by Petra Selmer
• GQL 2.0: A technical manifesto (:movie_camera: recording) (2022) by Alastair Green

Websites, encyclopedia entries

• GQL Standard
• The GQL Manifesto
• GQL Wikipedia page

Reference implementations and semantics

• :zap: Graph Pattern Matching in GQL and SQL/PGQ (preprint, 2021; paper at SIGMOD 2022) by Alin Deutsch et al.
  • talk by Leonid Libkin (ENS Paris): slides, :movie_camera: recording
• GQL Parser (2021) by Olof Morra (TU Eindhoven)
  • thesis
  • presentation

Posts, talks, podcasts

• SQL … and now GQL (2019) by Alastair Green
• GQL and openCypher: the road ahead (2019) by Alastair Green
• PostgreSQL, Oracle … graph query language standards adoption begins (2020) by Alastair Green
• Alastair Green on GQL: the Graph Query Language – The Graph Show
  • Query languages, Cypher, SQL/PGQ from 25:15 (~8 minutes)

Literature on graph processing

Dissertations and Master’s thesis works

• Query, Analysis, and Benchmarking Techniques for Evolving Property Graphs of Software Systems by Gábor Szárnyas – PhD dissertation, BME (2019)
  • :zap: Chapter 2 contains the background for graph databases
  • :star: Chapter 8 shows a mapping from openCypher queries to an extended relational algebra (it’s also available as a concise preprint)
  • :star: Section 10.5 summarizes the state of research (as of 2018) on mapping from graph queries to relational databases (see Table 10.2)
• :dizzy: Analysis and Comparison of Common Graph Query Languages by Martin Klampfer, TU Vienna (2020)
• :dizzy: A G-CORE Graph Query Language Interpreter by Georgiana Ciocirdel, CWI, VU Amsterdam (2018)
• Enabling Graph Analysis Over Relational Databases by Konstantinos Xirogiannopoulos – PhD dissertation, UMD (2019)
• Advanced Techniques for the Implementation of Model Transformation Systems (model/graph transformations in relational databases) by Gergely Varró – PhD dissertation, BME (2008)

Papers

Graphs as relational data

• LIquid: The soul of a new graph database, Part 2: this part of LinkedIn Engineering’s two-part series on the LIquid graph database discusses the representation of graphs as relational data and the limitations of naïve approaches (part 1 presents an object-oriented representation).

Graphs and SQL

• DuckPGQ: Bringing SQL/PGQ to DuckDB by Daniel ten Wolde, Gábor Szárnyas, Peter Boncz (VLDB 2023 demo)
• :zap: DuckPGQ: Efficient Property Graph Queries in an analytical RDBMS (slides, recording) by Daniel ten Wolde, Tavneet Singh, Gábor Szárnyas, Peter Boncz (CIDR 2023)
• :zap: Graph Processing in RDBMSs by Kangfei Zhao, Jeffrey Xu Yu (IEEE Data Eng. Bull., 2017)
  • Longer version: All-in-One: Graph Processing in RDBMSs Revisited (SIGMOD 2017)
• :zap: An Algebra and Equivalences to Transform Graph Patterns in Neo4j by Jürgen Hölsch, Michael Grossniklaus (GraphQ 2016)
• :star: GraphGen: Adaptive Graph Processing using Relational Databases by Konstantinos Xirogiannopoulos
• :star: Extending In-Memory Relational Database Engines with Native Graph Support by Mohamed S. Hassan, Tatiana Kuznetsova, Hyun Chai Jeong, Walid G. Aref, Mohammad Sadoghi (EDBT 2018) about GRFusion (SIGMOD demo), code
• :dizzy: Graph Pattern Matching – Do We Have to Reinvent the Wheel? by Andrey Gubichev, Manuel Then (GRADES 2014) :tv: slides
• Join Processing for Graph Patterns: An Old Dog with New Tricks by Dung T. Nguyen, Molham Aref et al. (GRADES 2015)
• G-SQL: Fast Query Processing via Graph Exploration by Hongbin Ma et al. (VLDB 2016)
• Cytosm: Declarative Property Graph Queries Without Data Migration by Benjamin A. Steer et al. (GRADES 2017)
• PGQL: a property graph query language by Oskar van Rest et al. (GRADES 2016)
• Extending SQL for Computing Shortest Paths by Dean De Leo and Peter Boncz (GRADES 2017) :tv: talk at the LDBC TUC 2017
• GraphWrangler: An Interactive Graph View on Relational Data, demo paper (SIGMOD 2019)
• Towards compiling graph queries in relational engines (DBPL 2019)

Graphs and SPARQL

• G-SPARQL: a hybrid engine for querying large attributed graphs by Sherif Sakr, Sameh Elnikety, Yuxiong He (CIKM 2012)

Semantics of graph query languages

• openCypher
  • Cypher: An Evolving Query Language for Property Graphs by Nadime Francis et al. (SIGMOD 2018), technical report on semantics
  • Updating Graph Databases with Cypher by Alastair Green et al. (VLDB 2019)
• G-CORE
  • G-CORE: A Core for Future Graph Query Languages by Renzo Angles et al. (SIGMOD 2018)

Overview papers and posts

• :zap: Graph query languages by Gábor Szárnyas (2021), the top 10 graph query languages
• Demystifying Graph Databases: Analysis and Taxonomy of Data Organization, System Designs, and Graph Queries by Maciej Besta et al. (preprint, 2020)
• Foundations of Modern Graph Query Languages by Renzo Angles et al. (ACM CSUR, 2017)
• A Survey Of Current Property Graph Query Languages by Peter Boncz (2020), talk
• The ubiquity of large graphs and surprising challenges of graph processing: Extended survey by Siddhartha Sahu et al. (VLDBJ 2020)

Talks

• :zap: :tv: The Linked Data Benchmark Council by Gábor Szárnyas and others (2020)
• :zap: :tv: Graph database applications with SQL/PGQ by Jan Michels, Andy Witkowski, Oracle (2020)
• :zap: :tv: Property Graph Extensions for the SQL Standard by Vasileios Trigonakis and Oskar van Rest, Oracle (LDBC TUC 2019)
• :tv: Mapping Graph Queries to PostgreSQL by Gábor Szárnyas et al. (2018)

Related

• :zap: :tv: PGQL Introduction and Deep Dive, an overview of PGQL by Melli Annamalai and Ryota Yamanaka, Oracle (2020)

Graph query engine implementations

• Morpheus: Cypher for Apache Spark (abandoned) :tv: slides
• CYpher TO Sql Mapper (Cytosm) (abandoned)
• ingraph: incremental graph queries (cypher-to-sql branch, abandoned)
• AgensGraph
• Apache AGE
• G-CORE Spark (G-CORE on Spark + GraphX, abandoned)
• Sparqling Kleene - Fast Property Paths in RDF-3X

Misc papers and talks

BFS

• An analysis of the SIGMOD 2014 Programming Contest: Complex queries on the LDBC social network graph by Márton Elekes et al. (technical report, 2020) and the BFS papers referenced in this report

Relational databases and property graphs

• On Directly Mapping Relational Databases to Property Graphs, AMW 2019
• SAP HANA Graph: blog post, tutorial, using the CREATE GRAPH WORKSPACE language construct

RDF systems

• Sparqling Kleene - Fast Property Paths in RDF-3X, GRADES 2013