7 min read




A selection of high level notes and links about NoSQL.

This is more a data dump than a presentation.

3 parts

  • Database & Models
  • Document Databases
  • Learnings

There is a lot of data in this presentation
The slides and links are available on acmconsulting.eu
I will be going fast

The basics

 Databases & Models

A database is a collection of information that is organized so that it can easily be accessed, managed, and updated.

A database model is a type of data model that determines the logical structure of a database and fundamentally determines in which manner data can be stored, organized, and manipulated.

Some revision

Relational Databases

This model organizes data into one or more tables (or “relations”) of columns and rows, with a unique key identifying each row.

Oracle, MySQL, MS SQL, PostgreSQL, DB2…. etc

Relational Databases - Popularity

Top scoring db engines

7 of the top scoring 10 systems are relational

Relational Databases - Details

Get on with it


A NoSQL (originally referring to “non SQL” or “non relational”) database [models it data] in means other than the tabular relations used in relational databasesWikipedia

NoSQL = All non relational databases

NoSQL - Details

NoSQL - Numbers?

Number of database systems per category, April 2016

60% of the available database engines are NoSQL!

NoSQL - Popular?

Ranking scores per category, April 2016

Only 18.3% of the score, for all NoSQL databases.
Document stores are the 2nd most popular category, 6.7%

Side note - CAP Theroem

A visual guide to NoSQL CAP

Consistency, Availability and Partition tolerance

CAP Theroem - Details

Tell us more about

Document Databases!


Document Database?

Document databases get their type information from the data itself, normally store all related information together, and allow every instance of data to be different from any other.Wikipedia

Document Databases - Scores

Document database score ranking, April 2016

MongoDB is the biggest player by far, ~70% share of all Document Database score

So lets look at MongoDB


MongoDB logo

MongoDB (from humongous) … eschews the traditional table-based relational database structure in favor of JSON-like documents with dynamic schemas (MongoDB calls the format BSON)

MongoDB - Details

  • Open Source (with commercial license option)
  • Commercial support
  • 4th highest scoring engine overall, and highest scoring document store
  • Database as a service from many providers, including MongoDB itself
  • Plenty of 3rd party apps, tools, drivers and support, more details
  • Jespen links : 2013, 2015
  • Sample Query : db.getCollection('user’).find({email: '[email protected]’, company: 'MongoDB’})

 MongoDB - NodeJS

Google trends for nodejs and mongodb

 MongoDB - NodeJS

NodeJS and MongoDB have “grow up together” and have become a very popular combination of technologies

Some MongoDB features (e.g. Map-Reduce) are used via writing Javascript functions

MongoDB - My thoughts

  • A top 10 database thats easy to use and focused on developer experience
  • Feels quite familiar to SQL users, but that can result in people trying to use it like an RDBMS, which is very bad
  • Had some early bad PR around issues of data loss and Jespen seems to break it
  • Loads of tutorials, easy to get started
  • Used in things like MEAN stack and KeystoneJS
  • Not a bad place to start

An Alternative


Couchbase logo

Couchbase Server, originally known as Membase, is an … NoSQL document-oriented database software package that is optimized for interactive applications.

 Couchbase - Details

  • 2nd highest scoring document store, but with only 8% of MongoBD’s score
  • Was formed by the merging of CouchOne (CouchDB) and Membase (Memcache)
  • Open Source (with commercial license option)
  • Commercial support
  • No off the shelf database as a service (that i could find), but they do have a number of partners to help you
  • Jespen link: none
  • Sample Query: SELECT * FROM users WHERE email='[email protected]’ AND WHERE type='userProfile’;

Couchbase - My thoughts

A Wild card



RethinkDB is an open source, NoSQL, distributed document-oriented database. It stores JSON documents with dynamic schemas, and is designed to facilitate pushing real-time updates for query results to applications.Wikipedia

ReThinkDB - Details

  • 7th highest scoring document store, but rising fast (was 11th)
  • Selling point is its realtime update feature, like firebase
  • Open Source
  • Commercial support
  • No off the shelf database as a service, yet, but one in the works. Horizon.io
  • Jespen links: 2016
  • Sample query: r.table('users’).filter({email: '[email protected]’, company: 'RethinkDB’})

ReThinkDB - My thoughts

  • Very nice UI and management interface, much like Couchbase
  • Only used for a side project, but enjoying using it
  • Installed on a raspberry pi 2, dealing with 250k object dataset with no issues and low cpu load
  • Not used the clustering/scaling/sharding
  • Can do joins!
  • http://horizon.io/ is potentially very interesting for rapid prototyping

Interesting developments

3 NodeJS Document stores

  • NodeJS “pure” databases, run as part of your node process, no external process or binary required
  • Great for little side projects or IOT applications
  • Quite a few of them, but 3 examples:

NodeJS Document store - PouchDB


inspired by Apache CouchDB … designed to run well within the browser. … enables applications to store data locally while offline, then synchronize it with CouchDB and compatible servers when the application is back onlinePouchDB

12th highest scoring document store,
but rising fast (was 16th)

NodeJS Document store - NeDB


Embedded persistent or in memory database for Node.js, nw.js, Electron and browsers, 100% JavaScript, no binary dependency. API is a subset of MongoDB’s

NodeJS Document store - TingoDB


TingoDB is an embedded JavaScript in-process filesystem or in-memory database upwards compatible with MongoDB at the API level.

The old dog/elephant?


PostgreSQL logo

As a document store?

JSONB turns the JSON document into a hierarchy of key/value data pairs … there’s support for GIN indexes

PostgreSQL - Details

  • 5th highest scoring db-engine, one behind MongoDB
  • Open Source (with commercial license option)
  • Commercial support
  • Lots of hosting options, including quite a few as a service
  • Jespen link: 2013
  • Sample Query: SELECT * FROM users WHERE email='[email protected]’ AND type='userProfile’;`

PostgreSQL - Some thoughts

  • I haven’t used JSONB except for experimentation
  • We do use it in production at work
  • Lead dev who uses it (Nick Johnson) had the following comments :
    • JSONB = JSON with Element Query + Indexes
    • Trade off is read/write speed vs standard JSON
    • Can even query nested objects
    • Keeps all RDBMS advantages (Joins, ACIDity, Materialized views)
    • Limited features compared to “full” document stores, but still very good.



  • It depends
    • (doesn’t it always)
  • Mongo is a safe choice due to adoption
  • Your use case may fit another better
  • Lots of innovation and experimentation going on
  • Its amazing what you can do with JavaScript

What did we learn about NoSQL?

NoSQL - Silver bullet?


Of course not.

  • NoSQL requires Non-relational thinking
  • Trying to use NoSQL as relational db == bad time
  • Joins in software works ok, until it doesn’t (i.e. at scale)

NoSQL - Schema less ness?

Just because it CAN be schema-less doesn’t mean it SHOULD be schema-less

NoSQL - What about joins?

  • Denormalization
    • Optimizes for reads, at the expense of writes/complexity
    • Tricky to keep things in sync (we’ve used hooks/micro-services)
    • Others suggest you don’t do it any more
  • Increasingly NoSQL engines do support limited forms of joins!

NoSQL - Same old problems

  • Data migration and schema changes are still as much “fun” as they ever were

NoSQL - Final thought

“NoSQL, or rather NoAuthentication, has been a huge gift to the hacker community. Just when I was worried that they’d finally patched all of the authentication bypass bugs in MySQL, new databases came into style that lack authentication by design.”
ArsTechinca “hacking team gets hacked”

Go Play

Have fun!


Presentation written in Markdown
Presented using Reveal.js / Reveal-MD
By Alex McFadyen
With help from the BEN Development team
Scoring screenshots from http://db-engines.com