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Today, I would like to talk to you about whether the data model is made up of data structure, data type and data operation. Many people may not know much about it. In order to make you understand better, the editor summarized the following for you. I hope you can get something from this article.

The data model usually consists of three parts: data structure, data operation and integrity constraints.

In general, a data model is a strictly defined set of concepts. These concepts accurately describe the static characteristics, dynamic characteristics and integrity constraints of the system, so the data type is usually composed of data structure, data operation and integrity constraints.

Related introduction:

Data model (Data Model) is the abstraction of data features. Data (Data) is a symbolic record that describes things, and Model (model) is an abstraction of the real world. The data model describes the static characteristics, dynamic behavior and constraints of the system from the abstract level, and provides an abstract framework for the information representation and operation of the database system. The data model describes three parts: data structure, data operation and data constraint.

The content described by the data model includes three parts: data structure, data operation and data constraint.

1) data structure: it mainly describes the type, content, nature and relationship of data, which is a collection of target types. The target type is the component of the database, which can be divided into two categories: data type and the relationship between data types. Data types such as records, data items in DBTG (database task group) mesh model, relationships and domains in relational model, etc. The connection part includes the system type of DBTG mesh model and so on. Data structure is the foundation of data model, and data operations and constraints are basically based on data structure. Different data structures have different operations and constraints.

2) data operation: the data operation in the data model mainly describes the operation type and operation mode on the corresponding data structure. It 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: the data constraints in the data model mainly describe the syntax, semantic relations, constraints and dependencies among the data within the data structure, as well as the rules of dynamic changes of the data to ensure the correctness, effectiveness and compatibility of the data. It is a collection of integrity rules that define the state of the database that conforms to the data model, as well as changes in state. 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.

After reading the above, do you have any further understanding that the data model is made up of data structures, data types and data operations? If you want to know more knowledge or related content, please follow the industry information channel, thank you for your support.

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