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New to MongoDB? This talk will introduce the philosophy and features of MongoDB. We’ll discuss the benefits of the document-based data model that MongoDB offers by walking through how one can build a simple app to store books. We’ll cover inserting, updating, and querying the database of books. This session will jumpstart your knowledge of MongoDB development, providing you with context for the rest of the day's content.
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SA, MongoDB
Norberto Leite
#mongodbdays @mongodb @nleite #developers
Building your first appAn introduction to MongoDB
First Things First!
Let’s not talk about Fußball!
Welcome to MongoDB Days Munich!
This is YOUR conference!
Thanks for being part of the Family!
Grab our staff for anything you need!
What is MongoDB?
MongoDB is a ___________ database
• Document
• Open source
• High performance
• Horizontally scalable
• Full featured
Document Database
• Not for .PDF & .DOC files
• A document is essentially an associative array
• Document = JSON object
• Document = PHP Array
• Document = Python Dict
• Document = Ruby Hash
• etc
Open Source
• MongoDB is an open source project
• On GitHub
• Licensed under the AGPL
• Started & sponsored by MongoDB Inc (formerly 10gen)
• Commercial licenses available
• Contributions welcome
High Performance
• Written in C++
• Extensive use of memory-mapped files i.e. read-through write-through memory caching.
• Runs nearly everywhere
• Data serialized as BSON (fast parsing)
• Full support for primary & secondary indexes
• Document model = less work
Database Landscape
Full Featured
• Ad Hoc queries
• Real time aggregation
• Rich query capabilities
• Strongly consistent
• Geospatial features
• Support for most programming languages
• Flexible schema
Setting Expectations
• What is MongoDB
• How to develop with MongoDB
• Scale with MongoDB
• Analytics
• MMS
• Sharding
• Setting the correct environment
Ready to become a Pro!
mongodb.org/downloads
$ tar –z xvf mongodb-osx-x86_64-2.6.5.tgz
$ cd mongodb-osx-i386-2.4.4/bin
$ mkdir –p /data/db
$ ./mongod
Running MongoDB
MacBook-Air-:~ $ mongoMongoDB shell version: 2.6.5connecting to: test> db.test.insert({text: 'Welcome to MongoDB'})> db.test.find().pretty(){
"_id" : ObjectId("51c34130fbd5d7261b4cdb55"),"text" : "Welcome to MongoDB"
}
Mongo Shell
Document Database
Terminology
RDBMS MongoDB
Table, View ➜ Collection
Row ➜ Document
Index ➜ Index
Join ➜ Embedded Document
Foreign Key ➜ Reference
Partition ➜ Shard
Let’s Build a Blog
Let’s Build a Blog
Let’s Build a Personal Data Hub!
First step in any application is
Determine your entities
Entities in our Data Hub
• Accounts
• Messages– emails– tweets– comments– streams
• Notifications
In a relational base app
We would start by doing schema design
Typical (relational) ERD
Messages
Tweets
messages
Accounts
Alerts
Das ist beängstigende Sache
In a MongoDB based appWe start building our appand let the schema evolve
MongoDB ERD
Accounts
Alerts
- account- user- password- refresh_rate- uri
Messages
- text- user- time- retweets
- from- to- body- attachments
- id- time- account_id
- subscribers- channel- rate- period- metrics:[]
…
Working With MongoDB
Demo time
>db
test
> use datahub
switching to db datahub
Switch to Your DB
>var account = {
"name": "gmail",
"credentials": {
"user": "[email protected]",
"password": "YOU WISH!"
},
"smtp": "smpt.gmail.com",
"tls": true
}
Create our first Document
>db
test
> use datahub
switching to db datahub
> db.accounts.insert( account )
Switch to Your DB
> db.accounts.insert(account)
Insert the Record
No collection creation necessary
> db.accounts.findOne()
{
"_id": ObjectId("54490561150027cc775b1019"),
"name": "gmail",
"credentials": {
"user": "[email protected]",
"password": "YOU WISH!"
},
"smtp": "smpt.gmail.com",
"tls": true
}
Find One Record
_id
• _id is the primary key in MongoDB
• Automatically indexed
• Automatically created as an ObjectId if not provided
• Any unique immutable value could be used
ObjectId
• ObjectId is a special 12 byte value
• Guaranteed to be unique across your cluster
• ObjectId("50804d0bd94ccab2da652599") |----ts-----||---mac---||-pid-||----inc-----| 4 3 2 3
> db.accounts.findOne()
{
"_id": ObjectId("54490561150027cc775b1019"),
"name": "gmail",
"credentials": {
"user": "[email protected]",
"password": "YOU WISH!"
},
”last_access": ISODate("2014-10-30T13:09:36.724Z"),
"smtp": "smpt.gmail.com",
"tls": true
}
Rich Data Types
Strings
Date
Boolean
BSON
> db.messages.insert({
"_id" : ObjectId("54527e08257844421e64623f"),
"favorited" : false,
"contributors" : null,
"truncated" : false,
"text" : "converting to #java 8",
"in_reply_to_status_id" : null,
”hashtags”: [ "#java", ]
…
}
Inserting Messages (emails, tweets …)
> db.messages.insert({
"_id" : ObjectId("54523d2d25784427c6fabce1"),
"From" : "[email protected]",
"To" : "[email protected]",
"Date" : ISODate("2012-08-15T22:32:34Z"),
"body" : {
"text/plain" : ”Hello Munich, nice to see yalll!"
},
"Subject" : ”Live From MongoDB World"
})
Inserting Messages (emails, tweets …)
> db.message.find().pretty(){
"_id" : ObjectId("54523d2d25784427c6fabce1"),
"From" : "[email protected]",
"To" : "[email protected]",
"Date" : ISODate("2012-08-15T22:32:34Z"),
"body" : {
"text/plain" : ”Hello Munich, nice to see yalll!"
},
"Subject" : ”Live From MongoDB World"
}
{
"_id" : ObjectId("54527e08257844421e64623f"),
"favorited" : false,
"contributors" : null,
"truncated" : false,
"text" : "converting to #java 8",
"in_reply_to_status_id" : null,
”hashtags”: [ "#java", ]
…
}
Finding a Message
> db.article.find({"hashtags":"#java"}).pretty(){
"_id" : ObjectId("54527e08257844421e64623f"),
"favorited" : false,
"contributors" : null,
"truncated" : false,
"text" : "converting to #java 8, #programing ",
"in_reply_to_status_id" : null,
”hashtags”: [ "#java", "#programing"]
…
}
Querying An Array
query in JSON
> db.messages.update({
"_id" : ObjectId("54523d2d25784427c6fabce1") },
{$set: { opened:
{date: ISODate("2012-08-15T22:32:34Z"), user:
’Norberto'}
}
})>
Using Update to Add a Comment
set new field on the document
which is a subdocument
> db.message.findOne({"_id" : ObjectId("54523d2d25784427c6fabce1")})
{
"_id" : ObjectId("54523d2d25784427c6fabce1"),
"From" : "[email protected]",
"To" : "[email protected]",
"Date" : ISODate("2012-08-15T22:32:34Z"),
"body" : {
"text/plain" : ”Hello Munich, nice to see yalll!"
},
"Subject" : ”Live From MongoDB World”
"opened" : {"date": ISODate("2012-08-15T22:32:34Z"), "user": ’Norberto'}
}
Post with Comment Attached
Find document by primary key
MongoDB Drivers
Real applications are not built in the shell
MongoDB has native bindings for over 12 languages
Morphia
MEAN Stack
Java
Python
Perl
Ruby
Support for the most popular languages and frameworks
Great, I’m excited! What’s next?
docs.mongodb.org
Never Stop Learning!
Schema Design, Schema Design, Schema Design, Schema Design!
Legacy Migration
1. Copy existing schema & some data to MongoDB
2. Iterate schema design developmentMeasure performance, find bottlenecks, and embed
1. one to one associations first2. one to many associations next3. many to many associations
3. Migrate full dataset to new schema
New Software Application? Embed by default
Embedding over Referencing • Embedding is a bit like pre-joined data
– BSON (Binary JSON) document ops are easy for the server
• Embed (90/10 following rule of thumb)– When the “one” or “many” objects are viewed in
the context of their parent– For performance– For atomicity
• Reference– When you need more scaling– For easy consistency with “many to many”
associations without duplicated data
It’s All About Your Application
• Programs+Databases = (Big) Data Applications
• Your schema is the impedance matcher– Design choices: normalize/denormalize,
reference/embed– Melds programming with MongoDB for best of
both– Flexible for development and change
• Programs×MongoDB = Great Big Data Applications
We've introduced a lot of concepts here
IoT
MMS @
Scale Easily
Best Practices, Automated
Cut Management Overhead
Scalability @
DevOps @
Provision
Upgrade
Scale
Continuous Backup
Point-in-Time Recovery
Performance Alerts
Wrapping up …
• MongoDB is a great Developers Tool
• Designed for :
• Scalability• Flexibility • Performance
• Multipurpose
• Great Ecosystem
Well Done !
Questions?
