Data model concepts
To understand DynamoDB better, we need to understand its data model first. DynamoDB's data model includes Tables, Items, and Attributes. A table in DynamoDB is nothing but what we have in relational databases. DynamoDB tables need not have fixed schema (number of columns, column names, their data types, column order, and column size). It needs only the fixed primary key, its data type, and a secondary index if needed, and the remaining attributes can be decided at runtime. Items in DynamoDB are individual records of the table. We can have any number of attributes in an item.
DynamoDB stores the item attributes as key-value pairs. Item size is calculated by adding the length of attribute names and their values.
DynamoDB has ...