Serverless Developer Guide
Data access is generally predictable and fast, in the millisecond (ms) range. If you need even faster 
response time, the DynamoDB Accelerator (DAX) provides in-memory acceleration for microsecond 
level access to data.
Traditional web frameworks maintain persistent network connections to SQL databases with
connection pools to avoid latency accessing data. With serverless architecture and DynamoDB, 
connection pools are not necessary to rapidly connect and scale the database. Instead, you can 
adjust your tables' throughput capacity, as needed.
What is DynamoDB? 73