This document provides an overview and introduction to MongoDB. It discusses how new types of applications, data, volumes, development methods and architectures necessitated new database technologies like NoSQL. It then defines MongoDB and describes its features, including using documents to store data, dynamic schemas, querying capabilities, indexing, auto-sharding for scalability, replication for availability, and using memory for performance. Use cases are presented for companies like Foursquare and Craigslist that have migrated large volumes of data and traffic to MongoDB to gain benefits like flexibility, scalability, availability and ease of use over traditional relational database systems.

1. 1
Big Data: MongoDB Workshop

2. 2
Content
▪ MongoDB Intro
▪ MongoDB @VRT by Chris
▪ MongoDB 2.6: What is new
▪ Break
▪ Certification by Tim
▪ Online Courses MongoDB / Hadoop and What next

3. 3
MongoDB Intro
▪ A new world
▪ NoSQL
▪ What is MongoDB
▪ MongoDB Architecture

4. 4
A New World
▪ New Apps
The applications serving, generating and interfacing with data have changed. Big Data,
SaaS, social and mobile apps are the new norm.
▪ New Data Types
New applications, users and inputs demand new types of data, like unstructured, semi-
structured and polymorphic data.
▪ New Data Volumes
Data volumes were once smaller, constrained and predictable. Today organizations must be
prepared to support millions of users, thousands of queries per second and hundreds of
terabytes of data.
▪ New Development Methods
The methods we use to build applications have changed. With increasingly competitive
markets and the need to adapt constantly, iterative development has become the standard.
▪ New Architectures
The infrastructure on which we store data has changed. Companies are leveraging cloud
computing, commodity hardware and virtualization.
MongoDB was designed for how we build and run applications today.

5. 55
NoSQL

6. 6
NoSQL
▪ Wide variety of different database techonologies
▪ Designed to deal with new issues arising with data
- Rise in volume of data stored
- Frequency in which this data is accessed
- Performance and Processing Needs
What is NoSQL

7. 7
NoSQL
▪ Document databases
- Pair each key with a complex data structure known as a document.
Documents can contain: key-value pairs, key-array pairs and even nested
documents.
▪ Graph stores
- Store information about networks, such as social connections.
▪ Key-value stores
- simplest NoSQL databases.
- every single item in the database is stored as an attribute name (or "key"),
together with its value.
▪ Wide-column stores
- Optimized for queries over large datasets
- Store columns of data together, instead of rows.
NoSQL datatypes

8. 8
The benefits of NoSQL
▪ More Scaleable
▪ More performance
▪ Their data model addresses several issues a relational model is not
designed to address
- Large volumes of structured, semi-structured, and unstructured data
- Agile sprints, quick iteration, and frequent code pushes
- Object-oriented programming that is easy to use and flexible
- Efficient, scale-out architecture instead of expensive, monolithic
architecture

9. 9
The benefits of NoSQL
▪ Dynamic Schemas
- Agile development approach
▪ Auto Sharding
- Application does not need to be aware of server composition
- Cloud
▪ Replication
- Most support automatic replication
- High availability and better disaster recovery
▪ Integrated Caching
- On relational DB does not improve writes

10. 1010
MongoDB

11. 11
What is MongoDB
▪ Open Source Database
▪ Used by companies of all sizes
▪ Agile database
▪ With functionality of traditional databases:
- Full query language
- Consistency
- Secondary Indexes
▪ Built for:
- Scalability
- Performance
- High Availability
▪ NoSQL

12. 1212
MongoDB
Architecture

13. 13
MongoDB Architecture
▪ Document Data Model
▪ Rich Query Model
▪ Idiomatic Drivers
▪ Horizontal Scalability
▪ High Availability
▪ In-Memory Performance
▪ Flexibility
Feature Overview

14. 14
MongoDB Architecture
▪ Data as Documents
- Stored in BSON (Binary Json)
- Collections (similar like a table tables)
- Tends to have all data for a given record in a single document
▪ Dynamic Schema
- Documents can vary in structure
- Fields can vary from document to document
- Documents are self-describing
- New fields, collections can be created without affecting all other documents
in the system, without updating a central system catalog and without
taking the system offline
MongoDB Data Model

15. 15
MongoDB Architecture
▪ Idiomatic Drivers
- MongoDB provides native drivers for all popular programming languages
and frameworks to make development natural.
- Supported drivers include Java, .NET, Ruby, PHP, JavaScript, node.js,
Python, Perl, PHP, Scala and others.
▪ Query Types
- MongoDB supports many types of queries. A query may return a document
or a subset of specific fields within the document.
▪ Key-Value queries: on alue of a specific field
▪ Range queries: on inequalities (greater then, smaller then …)
▪ Geospatial queries: on proximity criteria
▪ Text Search queries: on relevance order based on text arguments
▪ Aggregation Framework queries: like group by statements
▪ MapReduce Queries: complex data processing expressed in JavaScript
MongoDB Query Model

16. 16
MongoDB Architecture
▪ Indexing
- Many types of indexes on any field in the document
- Improve performance of some operations by orders of magnitued
- Has associated costs in the form of:
▪ Slower writes
▪ Disk usage
▪ Memory Usage
MongoDB Query Model

17. 17
MongoDB Architecture
▪ Auto-Sharding
- Distributes data across multiple physical partitions called shards.
- Allows MongoDB deployments to address the hardware limitations of a
single server, such as bottlenecks in RAM or disk I/O, without adding
complexity to the application.
▪ Sharding is transparent to applications:
- Applications issue requests to query routers which sends that query to the
appropriate shards
MongoDB Data Management

18. 18
MongoDB Architecture
▪ Transaction Model
- ACID compliant at the document level. Ensures complete isolation as a
document is updated; any errors cause the operation to roll back and
clients receive a consistent view of the document
- This is the same model used by many traditional relational databases to
provide durability guarantees.
- As a distributed system: additional flexibility in enabling users to achieve
their desired durability goals by controlling how write operations are
persisted across replicas.
MongoDB Consistency & Durability

19. 19
MongoDB Architecture
▪ Replica Sets
- MongoDB maintains multiple copies of data called replica sets
- A fully self-healing shard that helps prevent database downtime.
- Replica failover is fully automated,
- The number of replicas in a MongoDB replica set is configurable,
- A larger number of replicas provides increased data durability and
protection against database downtime (e.g., in case of multiple machine
failures, rack failures, data center failures, or network partitions).
- Optionally, operations can be configured to write to multiple replicas before
returning to the application, thereby providing functionality that is similar to
synchronous replication.
- Replica sets also provide operational flexibility by providing a way to
upgrade hardware and software without requiring the database to go
offline.
MongoDB Consistency & Durability

20. 20
MongoDB Architecture
▪ In-Memory Performance with On-Disk Capacity
- A fully self-healing shard that helps prevent database downtime.
- Extensive use of RAM to speed up database operations.
▪ Reading data from memory is measured in nanoseconds, whereas reading data
from spinning disk is measured in milliseconds; reading from memory is
approximately 100,000 times faster than reading data from disk.
- All data is read and manipulated through memory-mapped files. Data that is
not accessed is not loaded into RAM.
- While it is not required that all data fit in RAM, it should be the goal of the
deployment team that indexes and all data that is frequently accessed
should fit in RAM.
- If the volume of data that is frequently accessed exceeds the capacity of a
single machine => Automatic Sharding.
- No need for a separate caching layer.
MongoDB Consistency & Durability

21. 2121
MongoDB
Scale & Use Cases

22. 22
MongoDB Scale
▪ 30 of the world’s 100 largest organizations use MongoDB.
▪ Scale
- Over 100 organizations run clusters with more than 100 nodes. Some
clusters exceed 1,000 nodes.
- Deployments like: Yandex
▪ Velocity
- Many clusters deliver hundreds of thousands of operations per second
(combined read and write).
- Deployments like: Foursquare
▪ Volume
- Clusters with hundreds of terabytes, some store multiple petabytes of data.
- Over 150 clusters exceed 1 billion documents in size. Many with more than
100 billion documents.
- Deployments like: Craigslist

23. 23
MongoDB Use Case
▪ Why move?
- Original architecture relied on relational DB
- Too much traffic for 1 machine
▪ Why MongoDB
- Auto-sharding to scale high-traffic and fast-growing application
- Geo-indexing for easy querying of location-based data
- Dramatically simplified data model
Foursquary

24. 24
MongoDB Use Case
▪ In today’s regulatory environment, there are two constants about
compliance:
- requirements are changing
- the volume of data to manage is immense.
▪ For Craigslist, the popular classifieds and job posting community that
serves 570 cities in 50 countries, this means:
- Having to archive years of accumulated data. (1.5 million new classified
ads posted every day)
- Must be able to query and report on these archives at runtime.
▪ Historically:
- MySQL Cluster
- Simple schema change on their vast archive took months to complete,
preventing them from pushing new features.
Craigslist 1

25. 25
MongoDB Use Case
▪ Flexibility
- Each post and its metadata in a single document
- Schema changes with little cost
▪ Scalability and Availability
- Can to scale horizontaly across commodity hardware without having to
write and maintain complex, custom sharding code
- Craigslist’s initial MongoDB deployment was designed to hold over 5 billion
documents and 10TB of data.
- MongoDB’s support for automated failover of nodes via replica sets was
another big win. In the previous system it was a manual effort.
▪ Ease of Use
▪ Proven, Supported Technology
- Compared to the other NoSQL options, MongoDB is broadly-used
technology with many major deployments.
Craigslist 2

26. 2626
Questions ?