Session on NoSQL Databases and MongoDB. I stole the title from someone who deserves credit, but unfortunately, can't remember who. I blame the acid.

1. NoSQL - Death to Relational
Databases
Mike Feltman
F1 Technologies

2. Agenda
• The NoSQL Movement
• MongoDB Discussion & Demo
• Discussion

3. The NoSQL Movement
No SQL Databases:
Non-relational
Less ACID
More BASE
CAP Trading
Highly Scalable
Highly Performant
NoSQL = Not Only SQL

4. Less ACID
• Atomic
• basically means supports transactions
• Consistent
• Has hard constraints & rejects non-conforming data
• Isolated
• No peaking at incomplete commits
• Durable
• Once a commit is finished, it lasts forever.

5. More BASE
• Basically Available
• Soft-state
• Eventually consistent

6. CAP Trading
• Consistency (client perceives set of operations
completed)
• Availability (operations terminate with an
expected result)
• Partition tolerance (operations will complete,
even if a required resource is unavailable)
• Only 2 are possible in distributed systems.
– Eric Brewer

7. The NoSQL Movement
Why:
• SQL is tedious and difficult
• Strongly typed schemas are inflexible and
painful to maintain
• Inadequate performance of RDBMS on huge
data stores
• Poor Scalability of RDBMS
• Poor Replication Support

8. Types of NoSQL Databases
• Document Stores
• Graph
• Key/Value Store
• Object Database
• Tabular

9. Major Players
• Mongodb (10gen) • Dynamo (Amazon)
• CouchDB (Apache) • MObStor (Yahoo)
• Cassandra (Apache – • Haystack (Facebook)
formerly Facebook) • Voldemort (LinkedIn)
• BigTable – (Google) • HBase/Hadoop (Apache
• Berkeley DB (Oracle) & Microsoft)

10. MongoDB
Combining the best features of
document databases, key-value
stores, and RDBMSes.
• Scalable
• High-Performance
• Open Source
• Schema-free
• Document Oriented

11. MongoDB Features
• Document-oriented • Replication
storage (BSON) • Auto-sharding
• Dynamic Queries • MapReduce
• Full index support • Driver support for many
(including embedded languages
objects & arrays) • Cross-Platform
• Fast, in-place updates • Admin Tools
• Efficient Blob storage

12. Document Oriented Storage
{ firstName: “Nicklas”,
• Data is stored in BSON lastName: “Lidstrom”,
– Binary-encoded team: “Red Wings”,
serialization of JSON-like stanleyCups : [1997, 1998,
documents. 2002, 2008],
– Lightweight, traversable norrisTrophies : [2001,
& efficient 2002, 2003, 2006, 2007,
– Supports embedded 2008] }
objects & arrays
– Document = Record

13. Dynamic Queries
• No indexes required to Examples
find data. • All records:
• RDBMSes all support db.players.find({})
this as well. • All Red Wings
db.players.find({“team”:
“Red Wings”})

14. Index Support
• B-Tree format
• Default index on PK
• Supports unique, compound, document
indexes (indexes on nested documents) and
multikeys indexes (allows indexing of arrays of
values)

15. Fast in-place updates
• Updates are made to existing documents
within a collection.
• Many “NoSQL” databases (such as CouchDB)
do not support updates and instead store
versions of records.

16. Efficient Blob Storage
• Blob = Binary Large Object
• Up to 4MB within document
• GridFS specification is followed for larger
items and external files

17. Replication
• Enhanced master-slave configuration
– one server active for writes at a time.
– Provides failover and redundancy
– Implemented with Replica Pairs
• When master fails slave takes over
• When slave fails control reverts to master
• Limited Master-master

18. Auto-Sharding
• Sharding:
– Breaking database down into “shards” and
spreading those across distributed/commodity
servers.
– highly scalable approach for increased throughput
and performance of high-transaction, large
database applications.
– MongoDB manages data storage and retrieval
behind the scenes.

19. MapReduce
• Useful for batch
• Term comes from Google. operations
– Patented framework for • Aggregation: NoSQL
processing huge datasets answer to GROUP BY
on certain kinds of
distributable problems
using a large number of
servers.
– MongoDB applies it to
single server instances as
well.

20. Drivers
• .NET (C#) • Perl
• JavaScript • JVM
• Python – Clojure
• PHP – Groovy
– Scala
• Ruby
• Java
• C++

21. Cross-Platform
• 32 bit & 64 bit versions available for:
– Windows
– OS X
– Linux
– Solaris

22. Admin Tools
• Command Shell
• Simple limited REST (http) Interface
• Mongostat
• Mongosniff (Unix only – use tcpdump on
Windows)
• Backup & Restore

23. MongoDB Terminology
Traditional RDBMS MongoDB
• Database • Database
• Table • Collection
• Record • Document
• Field • Key

24. Demo!
• Start the server (if it’s not running).
C:mongodbbinmongod
• Start the shell
C:mongodbbinmongo

25. The MongoDB Shell

26. Database Commands
• Open Database • use (database name)
• Create Database • use (database name)

27. How it works
• Focused on documents
– Document = sequence of key value pairs in bson
• Value can be another document
• Additional types vs. JSON. ie dates, regexp
• Messages (cpassed over TCP/IP) in BSON drivers convert code to BSON
• Memory mapped storage engine (MMSE) – all disk access takes place
through MMSE
• Query Optimizer:
– Find( {x:10, y:”foo”})
– Launches multiple simultaneous queries based on indexes & table scan. Stops
when one finishes, remembers which one was the fastest for future similar
queries. Can use hint option to specify which index to use.

28. Why?
• Applications where schema gets in the way
• Performance
• Scalability
• RAD
• More natural fit with OO Languages

29. Resources
• www.mongodb.org