Dgraph: Fast graph database written in Go

The talk was given at Gophercon Singapore.

Link to video: https://www.youtube.com/watch?v=cHXbYLNa0qQ

Transcript

1. Dgraph: Fast graph database written in Go Manish R Jain Dgraph Labs
2. 1. Introduction: Hi, Diggy!
3. What are graph databases Optimized for key-value lookups AND edge traversals ( joins ).
4. What is Dgraph? Dgraph is an open source graph database built for web-scale production environments written entirely in Go. Fast Sharded and Distributed (Distributed Joins, Filters and Sorts) Horizontally scalable Consistent Replication via Raft Highly Available by design Fault tolerant
5. Why build it? Any company doing anything smart is using graphs. No native scalable solution.
6. Concepts SUBJECT - predicate -> OBJECT // Facts <SINGAPORE> <neighbor> <MALAYSIA> . <SINGAPORE> <neighbor> <INDONESIA> . // Half facts <SINGAPORE> <national_drink> <MILO> . SUBJECT - predicate -> Value <SINGAPORE> <name> "Singapore" .
7. Reception v0.1 release in Dec '15 3200 Github stars 32 contributors Next release: v0.8 First page of HN multiple times. news.ycombinator.com/item?id=11322444 (https://news.ycombinator.com/item?id=11322444)
8. 2. Benchmarks
9. Neo4j Neo4j data loading Dgraph is 100x faster. Neo4j query Dgraph is 3x-6x faster on a read-write workload. At least as fast on read-only. Link to full benchmark code (https://github.com/dgraph-io/benchmarks/tree/master/data/neo4j)
10. Cayley (with Bolt on Macbook) Cayley is a graph layer written in Go. Loading 21M RDFs Dgraph is 9.7x faster Queries Dgraph is 5x - 36.6x faster Link to full benchmark code (https://github.com/ankurayadav/graphdb-benchmarks)
11. 3. Using a graph database
12. Graph-y questions (1/2) Are they an overkill? Are they robust? Are they scalable?
13. Graph-y questions (2/2) Are they an overkill? No Are they robust? Yes Are they scalable? Yes
14. Your SQL DB is slowing you down (1/3) SQL is like C, Graph query language is like Go or Python. Just like high level languages allow you to express logic faster, Databases allowing more complex queries allow you to iterate on your application faster. They achieve this by cutting down your application code by at least half.
15. Your SQL DB is slowing you down (2/3) What SQL forces you to do: Because SQL does lesser things, you need to do more things. Maintain a strict schema. Data duplication to avoid slow joins. Pre-compute counts for foreign tables to allow e cient sorting.
16. Your SQL DB is slowing you down (3/3) What Dgraph does: Flexible sparse schema, with real time modi able data types. Join is a single lookup away, so no data duplication. Simplify schema. Any counts can be done cheaply in real time.
17. 4. Demo: Run Stack Over ow on Dgraph
18. User Schema SQL | Dgraph --- | ------ Reputation | Reputation CreationDate | CreationDate DisplayName | DisplayName LastAccessDate | LastAccessDate Location | Location AboutMe | AboutMe Age | Age Views | UpVotes | DownVotes |
19. Versioning (SQL, Dgraph) SQL | Dgraph --- | ------ TypeId | Type PostId | Post (point to Post) CreationDate | CreationDate Author | Author Text | Text
20. Post SQL | Dgraph --- | ------ TypeId | Type ParentId | Has.Answer AcceptedAnswerId | Chosen.Answer Title (duplicate of versioning) | Title (point to Version) Body (duplicate of versioning) | Body (point to Version) Tags (duplicate of versioning) | Tags (point to Version) OwnerUserId | Owner (point to User) Score | Score LastEditorUserId | LastEditDate | LastActivityDate | CommentCount | AnswerCount | FavoriteCount | CreationDate |
21. Comment, Vote SQL | Dgraph --- | ------ PostId (Vote/Comment -> Post) | (New edge from Post -> Vote/Comment) Timestamp | Timestamp Author | Author VoteType (for Vote) | Score (for both Vote and Comment) Text (for Comment) | Text (for Comment)
22. Dgraph Schema
23. Live Demo
24. Query 1: Top questions
26. Query 2: Question Page
27. 5. Final Thoughts
28. When to use Dgraph, when SQL SQL has a great use case, which is to provide ACID transactions. Great solution to store nancial data. For everything else, I think a well designed graph database is more ideally suited. Cuts down on the amount of coding e ort required, using the power of graphs to run complex queries.
29. Thank you Manish R Jain Dgraph Labs manish@dgraph.io (mailto:manish@dgraph.io) https://dgraph.io (https://dgraph.io)