DynamoDB Basics

DynamoDB is a managed key-value and document database that scales without servers to patch.

aws dynamodb create-table --table-name Orders \
  --attribute-definitions AttributeName=customerId,AttributeType=S \
                          AttributeName=orderId,AttributeType=S \
  --key-schema AttributeName=customerId,KeyType=HASH \
               AttributeName=orderId,KeyType=RANGE \
  --billing-mode PAY_PER_REQUEST --region ap-south-1

aws dynamodb put-item --table-name Orders \
  --item '{"customerId":{"S":"c1"},"orderId":{"S":"o100"},"total":{"N":"499"}}'
aws dynamodb query --table-name Orders \
  --key-condition-expression "customerId = :c" \
  --expression-attribute-values '{":c":{"S":"c1"}}'

Key points:

• The partition key spreads data; the optional sort key orders items within it. Queries need the partition key.
• Design the table for your access patterns; there are no joins. Use a secondary index for another pattern.
• On-demand capacity suits unpredictable load; provisioned with auto scaling suits steady load.
• Turn on point-in-time recovery and use TTL to expire old items.