What are the traditional basic data models?

There are three traditional basic data models:

1, hierarchical model

Hierarchical model is a tree structure model, which organizes data according to the natural hierarchical relationship to reflect the subordinate relationship between data. Hierarchical model is the earliest and most mature data model in database technology. Its characteristic is to organize geographic data into a directed and orderly tree structure, also called tree structure. Nodes in the structure represent data records, and connecting lines describe the subordinate relationship (one-to-many relationship) between data of different nodes.

2. Grid data model

The network model organizes data into a directed graph structure, in which nodes represent data records and lines describe the connections between data of different nodes. The basic feature of this data model is that there is no clear subordinate relationship between node data, and one node can establish contact with other nodes, that is, the contact between nodes is arbitrary, and any two nodes can have contact, which can represent a many-to-many relationship.

3. Relational data model

Relational database has developed rapidly because of its simple structure, convenient operation and solid theoretical foundation. Almost all database management systems introduced after 1980s are relational. The basic knowledge involved is: logical data structure of relational model, operators of tables, integrity rules of tables, and concepts of views and paradigms.

The relational model can simply and flexibly represent various entities and their relationships, and its data description has strong consistency and independence. In the relational database system, data manipulation is realized by relational algebra, which has a strict mathematical foundation.