In the field of database, we often divide different models according to the relationship between data. Hierarchical model, network model and relational model are three common database models, which have their own characteristics and are suitable for different scenarios.

hierarchical model

The basic structure of hierarchical model is like a tree, with distinct branches and leaves. It is suitable for scenarios with obvious hierarchical relationships between data, such as organizations and file directories.

network model

The grid model is an undirected graph without any restrictions, and the relationships between data can be freely connected. It is suitable for scenes with complex many-to-many relationship between data, such as drug research and library management.

relation model

The relational model uses two-dimensional tables to represent data, and pays more attention to the logical structure of data. It is suitable for scenarios where there is a simple one-to-one or one-to-many relationship between data, such as customer information and order information.