What are the concepts and classifications of data models in databases
The concept of data model in database is: data model is the abstraction of data characteristics. It describes the static characteristics, dynamic behavior and constraints of the system from an abstract level. Classification of data models: 1. Conceptual data model; 2. Structural data model.
The concept of data model:
The data model (Data Model) is an abstraction of data characteristics. It describes the system from an abstract level. Static characteristics, dynamic behaviors and constraints provide an abstract framework for information representation and operation of database systems.
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Classification of data models:
The most commonly used data models are conceptual data models and structural data Model:
1. Conceptual data model (information model): user-oriented, modeled according to the user's point of view, typical representative: E-R diagram
2. Structural data model: computer system-oriented For the implementation of DBMS, typical representatives include: hierarchical model, network model, relational model, object-oriented model
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