DGRAPH-ORM Not everything can fit in rows and columns By Ashok Vishwakarma 

WHO AM I? Naukri.com AVP - Engineering Google Developer Expert (GDE) Web Technologies & Angular Ashok Vishwakarma @avishwakarma @_avishwakarma 

THE RDBMS PROBLEM What RDBMS forces you to do? ● Maintain a strict schema ○ If you modify a column from string to float you have to do manual table migration. ● Data duplication to avoid slow joins ○ The same information is kept in multiple tables, to avoid joins. ● Pre-compute counts for foreign tables ○ To allow efficient sorting of data. 

NOSQL IS NOT A SOLUTION It’s a way out not a way in ● It kills the valuable relationship between data ○ Storing everything into a single document is not possible all the time. ● Data duplication is still there ○ We are force to put the same data in multiple documents ● ACID, Security and etc. 

THE SOLUTION A Graph Database. How it helps? ● Flexible sparse schema with real-time modifiable data types ○ Change predicate type from string to float without migration. ● No data duplication ○ Any join is single lookup. ● Counts are cheap in real time ○ Any sort can be perform on these counts efficiently. 

WHO USES GRAPH DATABASES? ● Google - NoEdgeGraph ● Facebook - FacebookTau ● Twitter - FlockDB ● Dropbox, Pinterest, Linkedin and etc have their own versions of graph layers Any company doing anything smart is using Graph Databases 

SO LET’S MOVE TO GRAPH DATABASE ● Single server or on top of other databases ○ Existing graphs either single server like Neo4j or they are hastily put together on other databases like Cayley, titanDB or DSCGraph. ● No standard ○ Companies have to built their graph systems. FcabeookTau, NoEdgeGraph FlockDB and etc. Wait! There are some problems with existing Graph Database solutions 

INTRODUCING DGRAPH An Open Source Graph Database written in Go ● Fast - Built like a search engine ● Sharded and Distributed with distributed joins, filters and sort ● Horizontally Scalable with consistent replication using Raft ● Highly available by design ● Fault-tolerant ● GraphQL+- Dgraph Query Language 

DGRAPH VS NEO4J & CAYLEY - BENCHMARK Neo4j ● 100x faster data loading ● 3x to 6x faster in querying data Cayley ● 9.7x faster data loading ● 5x to 36x faster in querying data 

MYTHS Should we really using Graph Database? ● Are they an overkill? ○ I might have to run some traversals should I use graphs or its an overkill. ● Are they robust? ○ Do I need to run a primary datastore so this graph database does not lose my data. ● Are they scalable? ○ I have to run lot of queries, can graph database achieve the performance and scale. 

MYTHS Should we really using Graph Database? ● Are they an overkill? ○ No! You should use a graph database they are not an overkill. ● Are they robust? ○ Yes! They can act like a primary datastore. ● Are they scalable? ○ Yes! They will scale, in fact Dgraph with sharded and distributed architecture scale better than mysql database stuck on a single server. 

DGRAPH-ORM dgraph-orm - Why we need an ORM? ● Dgraph uses GraphQL+- for it’s query language. ○ GraphQL is fine but that +- is tricky and require learning. ● We love Mongoose and Sequelize ○ Using similar ORM is easy to get started. ● Object based schema ○ Dgraph’s schema is string based 

user.name: string @index(term) . ... user.friend uid @count @reverse . // User.js import {Schema, model, Types} from 'dgraph-orm'; const UserSchema = new Schema('user', { name: { type: Types.STRING, index: true, token: { term: true } }, ... friends: { type: Types.UID, model: 'user', count: true, reverse: true } }); const User = model('user', UserSchema); 

import User from './user'; // Creating user const users = await User.create({ email: '[email protected]', password: '$ecureP@ssw0rd' }); // Querying users const users = await User.has('email', { filter: { email: '[email protected]' } }); # creating user { set { _:u1 '[email protected]' . _:u1 '$ecureP@ssw0rd' . } } # querying users { users(func: has(user.email)) @filter(eq(user.email, '[email protected]')) { uid email: user.email } } More Examples https://github.com/ashokvishwakarma/dgraph-orm 

Live Demo 

DGRAPH-ORM NPM https://www.npmjs.com/package/dgraph-orm GITHUB https://github.com/ashokvishwakarma/dgraph-orm Where can you find it? 

QUESTIONS? { ? }