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This article mainly introduces the types of models in the database, which are very detailed and have a certain reference value. Friends who are interested must finish reading them.

The classification of models in the database: 1, conceptual data model, user-oriented, real-world-oriented data model, describing the conceptual structure of a unit; 2, logical data model, can outline the data blueprint of the enterprise through entities and relationships; 3. Physical data model, with the characteristics of intuitive expression of cognitive objects in the form of physical objects or drawings.

Classification of models in the database:

1. Conceptual data model

The characteristic is that

A user-oriented, real-world-oriented data model that describes the conceptual structure of a unit

It has strong semantic expression ability, and can express all kinds of semantic knowledge in application conveniently and directly.

Simple, clear and easy for users to understand

Conceptual models are artifacts full of subjective colors.

2. Logical data model

The characteristic is that

It directly reflects the needs of the business department and plays an important role in guiding the physical implementation of the system.

The data blueprint of an enterprise can be drawn through entities and relationships.

The logical model provides a mechanism for user-defined integrity constraints to reflect the specific semantic constraints that the data involved in specific applications must comply with.

3. Physical data model

The characteristic is that

Have the characteristics of intuitively expressing cognitive objects in the form of physical objects or drawings.

Each logical data model has its corresponding physical data model when it is implemented.

Describe the organizational structure of data on the storage medium, not only related to the specific DBMS, but also related to the operating system and hardware.

Extended data:

Data model structure is mainly divided into data structure, data operation and data constraint.

The main contents are as follows: 1. Data structure mainly describes the type, content, nature and relationship of data. Data types, such as records in DBTG mesh model, data items, relationships in relational models, and so on. Data structure is the basis of data model, and different data structures have different operations and constraints.

2. Data operation mainly describes the operation type and operation mode on the corresponding data structure. Is a collection of operation operators, including several operations and inference rules, to operate on a database composed of valid instances of the target type.

3. Data constraints mainly describe the syntax, semantic relations, constraints and dependencies between them, as well as the rules of dynamic changes of data in the data structure, in order to ensure the correctness, effectiveness and compatibility of the data. According to different principles, constraints can be divided into data value constraints and data connection constraints; static constraints and dynamic constraints; entity constraints and reference constraints between entities.

The above is all the contents of the article "what are the types of models in the database". Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!

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