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Amazon home page for DynamoDB:

https://aws.amazon.com/dynamodb/

DynamoDB FAQs:

https://aws.amazon.com/dynamodb/faqs/

Limits in DynamoDB:

http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/Limits.html

Reserved Words in DynamoDB:

Amazon DynamoDB Accelerator (DAX) is a fully managed, highly available, in-memory cache for DynamoDB that enables you to benefit from fast in-memory performance for demanding applications. DAX improves the performance of read-intensive DynamoDB workloads so repeat reads of cached data can be served immediately with extremely low latency.

The DynamoDB Storage Backend for Titan is a plug-in that allows you to use DynamoDB as the underlying storage layer for Titan graph database.

It is a client side solution that implements index free adjacency for fast graph traversals on top of DynamoDB.  

Using DynamoDB enables you to run graph workloads without having to manage your own cluster for graph storage.

DynamoDB Time-to-Live (TTL) is a mechanism that lets you set a specific timestamp to delete expired items from your tables. Once the timestamp expires, the corresponding item is marked as expired and is subsequently deleted from the table. TTL can help you reduce storage usage and reduce the cost of storing data that is no longer relevant.

Use cases

There are two main scenarios where TTL can come in handy:

1. Fine Grained Access Control (FGAC) gives a DynamoDB table owner a high degree of control over data in the table.

2. The table owner can indicate who (caller) can access which items or attributes of the table and perform what actions (read / write capability).

3. FGAC is used in concert with AWS IAM, which manages the security credentials and the associated permissions.

These are notes on some useful APIs to work with GSI and LSI.

Query API (GSI/LSI)

GSI support Query and Scan.

In addition to the common query parameters, a Query command explicitly includes the name of the index to operate against.

A query can use only one index.

A Query operation only searches index key attribute values and supports a subset of comparison operators.

1. an index with a partition or a partition-and-sort key that can be different from those on the table.

2. "global" because queries on the index can span all items in a table, across all partitions.

3. GSI behavior is similar to that of a DynamoDB table: You can query a GSI using its partition key element, with conditional filters on the GSI sort key element.

1. an index that has the same partition key as the table, but a different sort key. E.g. tracks Orders for customers, where CustomerId is the partition key.

2. "local" in the sense that every partition is scoped to a table partition that has the same partition key.

3. When you query a LSI, DynamoDB can access any of the projected attributes, with the same performance characteristics as if those attributes were in a table of their own.

VM Import/Export enables you to easily import virtual machine images from your existing environment to Amazon EC2 instances and export them back to your on-premises environment.

AWS Lambda is a higher level abstraction that lets you run code without provisioning or managing servers, following the servlerless architecture. You can run code for virtually any type of application or backend service with no administration.

You just needs to upload your code and Lambda takes care of everything required to run and scale your code with high availability, such as server and operating system maintenance, capacity provisioning, automatic scaling, code and security patch deployment, code monitoring and even logging.