GraphQL is transforming data interaction by enabling developers to query disparate data sources through a unified API layer, exemplified by the creation of a supergraph using Hasura and AWS AppSync. This approach allows for seamless integration and querying of data from PostgreSQL and Amazon DynamoDB, creating a cohesive data graph that simplifies access and management. Hasura connects to PostgreSQL to auto-generate GraphQL APIs with advanced querying capabilities, while AWS AppSync facilitates the creation of a GraphQL API for DynamoDB. These individual subgraphs are then federated into a supergraph, allowing for comprehensive queries across both databases, as demonstrated in an e-commerce scenario where product and inventory data are queried together. Embracing supergraph architecture is vital for organizations seeking to unify and scale their data landscape efficiently, promoting a modular and scalable infrastructure by reducing the complexity of handling multiple APIs.