Install a Local Instance of AWS DynamoDB

STEP 1:  Press Command+Space and type Terminal and press enter/return key.

STEP 2:  Install Brew(If you don't already have it installed.)  Run this command in the Terminal app.

ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)" < /dev/null 2> /dev/null

Then press enter and wait for the command to finish.

STEP 3:  Use Brew to install and download dynamoDB so that you can run it locally.

brew install dynamodb-local

Launch your DynamoDB local instance like this:

To have start dynamodb-local now and restart at login as a background service using brew services:

  brew services start dynamodb-local

Or, if you don't want/need a background service you can just run:

  /usr/local/bin/dynamodb-local

You can then access a JS Shell in a browser such as Chrome:
URL to hit the Javascript shell for your locally running DynamoDB instance:

http://localhost:8000/shell/

This is what you will see what you load up your DynamoDB Shell.  If you see this, then you are successfully running a local instance of DynamoDB!

AWS Local DynamoDB Javascript Shell in Browser

Common DynamoDB Concepts

• Table:  A collection of data
• Items: An item is a group of attributes that is uniquely identifiable among all of the other items.
• Attributes: An attribute is a fundamental data element, something that does not need to be broken down any further.
• Primary Key
  • Partition Key:  Composed of one attribute known as the partition key
  • Partition Key and Sort Key: Composite primary key, composed of two attributes.

Datatypes
Scalar

• Number:  String
  • Example:  "N": "123.45"
• String:  String
  • Example:  "S": "Hello"
• Binary:  Base64-encoded binary data
  • Example:  "B": "dGhpcyB0ZXh0IGlzIGJhc2U2NC1lbmNvZGVk"
• Boolean:  Boolean
  • Example:  "BOOL": true
• Null:  Boolean
  • Example:  "NULL": true

Multi-value

• String Set:  Array of Strings
  • Example:  "SS": ["Giraffe", "Hippo" ,"Zebra"]

• Number Set:  Array of Strings
  • Example:  "NS": ["42.2", "-19", "7.5", "3.14"]

• Binary Set:  Array of Base64-encoded binary data
  • Example:  "BS": ["U3Vubnk=", "UmFpbnk=", "U25vd3k="]

Document

• List: array of AttributeValue objects
  • Example:  "L": ["Cookies", "Coffee", 3.14159]

• Map:  String to AttributeValue object map
• Example:  "M": {"Name": {"S": "Joe"}, "Age": {"N": "35"}}

Partition Key Hashing

Partition key uniquely identifies a item
Partition key is used for building an unordered hash index
Allows table to be partitioned for scale

Some further reading on DynamoDB

• https://aws.amazon.com/dynamodb/getting-started/
• What is noSQL and how is it implemented on AWS?
• Amazon DynamoDB: How It Works in the Amazon DynamoDB Developer Guide
• Sign up for a monthly webinar series:  https://aws.amazon.com/about-aws/events/monthlywebinarseries/?trkCampaign=WEBINARSERIES&trk=juneseries16homepage

References:

1. http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Introduction.html
2. http://docs.aws.amazon.com/amazondynamodb/latest/gettingstartedguide/Welcome.html
3. http://docs.aws.amazon.com/amazondynamodb/latest/APIReference/
4. https://en.wikipedia.org/wiki/Amazon_DynamoDB
5. https://github.com/derjust/spring-data-dynamodb
6. https://github.com/michaellavelle/spring-data-dynamodb
7. http://projects.spring.io/spring-data/
8. https://aws.amazon.com/nosql/
9. http://cloudacademy.com/blog/amazon-dynamodb-ten-things/
10. http://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_AttributeValue.html
11. http://www.slideshare.net/InfoQ/amazon-dynamodb-design-patterns-best-practices