Non-Relational Databases, also known as NoSQL databases, provide flexible and scalable solutions for managing large-scale data that doesn't fit into traditional table structures. They support a wide range of data models and are ideal for big data and real-time applications.
Non-Relational Databases are used by organizations that need to store and retrieve large amounts of unstructured or semi-structured data. They offer versatility in terms of data models, including document, graph,...
I find the price of Amazon SimpleDB to be relatively high compared to other solutions available in the market like Microsoft and other cloud services.