2. AWS DynamoDB
Is a key-value and document database that delivers single-digit millisecond performance at any scale. It's
a fully managed, multiregion, multimaster, durable database with built-in security, backup and restore,
and in-memory caching for internet-scale applications.
● DynamoDB was built on the principles in the original Dynamo paper
● Monitoring through CloudWatch
● Maximum item size is 400 KB
● Doesn't have SQL query language available
● Capacity Provisioned and On-demand
● Pay per provisioned capacity and storage usage
● Reads can be eventually consistent or strongly consistent
3. Queries and Indexes
● Can only query on primary key, sort key, or indexes
● Global secondary index — partition key and a sort key that can be different from those on the base
table, max 5
● Local secondary index — has the same partition key as the base table, but a different sort key, max
5
4. DAX(DynamoDB Accelerator)
● Fully managed, highly available, in-memory cache
● 10x performance improvement
● Reduces request time from milliseconds to microseconds – even at millions of requests per second
● No need for developers to manage caching logic
● Compatible with DynamoDB API calls
5. Transactions
● Multiple "all-or-nothing" operations
● Financial transactions
● Fulfilling orders
● Two underlying reads or writes - prepare/commit
● Up to 25 items or 4 MB of data
6. On-Demand Capacity
● Pay-per-request pricing
● Balance cost and performance
● No minimum capacity
● When table is idle no charge for read/write — only storage and backups
● Pay more per request than with provisioned capacity
● Use for new product launches
7. Backup and Restore
● On-Demand Backup and Restore
● Full backups at any time
● Zero impact on table performance or availability
● Consistent within seconds and retained until deleted
● Point-in-Time Recovery (PITR)
○ Protects against accidental writes or deletes
○ Restore to any point in the last 35 days
○ Incremental backups
○ Not enabled by default
○ Latest restorable: five minutes in the past
8. Streams
● Timed-ordered sequence of item-level changes in the table
● Stored for 24 hours
● Inserts, updates and deletes
● Combine with Lamda functions for functionally like stored procedures
9. Global Tables
● Managed multi-master, multi-region replication
● Globally distributed applications
● Based on DynamoDB streams
● Multi-region redundancy for DR or HA
● No application rewrites
● Replication latency under one second
● Last writer wins reconciliation between concurrent updates
10. Security
● Encryption at rest using KMS
● Site-to-site VPN
● Direct Connect (DX)
● IAM policies and roles
● Fine-grained acess
● CloudWatch and CloudTrail
● VPC endpoints
