Embodiments of the present invention provide systems and techniques for displaying data models and data-model instances. During operation, the system can use a model graph to represent the data model and an instance graph to represent the data-model instance. In the graph representation, a vertex can represent an entity or an entity instance, and an edge can represent a relationship or a relationship instance. The system can display the model graph and the instance graph, either separately or concurrently, thereby enabling the user to visually explore the data model and the data-model instance by exploring the associated graphs. The system can display paths in the graphs to the user, thereby enabling the user to visually explore how entities and entity instances are related to one another. The system can also enable a user to search for entities and relationships using various criteria.