dynamoDB Overview

Question 1

What are the key features of DynamoDB?

Answer 1

• serverless
• non-relational database service
• key-value data model
• managed service - requiring no patching or upgrading
• high throughput and single-digit latency at any scale
• suitable for high-traffic web applications or gaming applications
• scales automatically
• replicates across multiple availability zones (AZs) in a region by default
• built-in fault tolerance that adjusts capacity based on the number of requests
• can be accessed using SQL queries like PartiQL
• permissions are handled via IAM (Identity and Access Management).**

Question 2

What are the core components of DynamoDB?

Answer 2

• tables, items, and attributes
• an item is analogous to a row in a traditional database,
• an attribute is analogous to a column.

Question 3

What are primary keys in DynamoDB?

Answer 3

• used to uniquely identify each item
• can be a partition key or partition key + sort key (optional)
• The partition key identifies an item’s location
• sort key used for querying data and sorting the order of items that share the same partition key.

Question 4

What are the considerations when performing scans in DynamoDB?

Answer 4

• slow and less efficient, especially as the table grows larger.
• Each iteration of a scan operation consumes read capacity units
• avoid scans on large tables whenever possible.

Question 5

What is a secondary index in DynamoDB?

Answer 5

• contains a subset of attributes from a table, along with an alternate key to support query operations.
• It allows using non-key attributes as primary keys in query operations is different from the original table.
• When creating a secondary index, you can specify attribute projection, which determines which attributes are copied from the base table to the secondary index.

Question 6

What are the options for attribute projection

Answer 6

There are three options for attribute projection:
* Only Keys
* Include
* All.