There are 3 types of cardinality including
Examples of entities include customer, order, product, or category. Attributes : Attributes appear as columns in a specific table. Examples include product identifiers and product names (for Products) and category identifiers and category names (for Categories). Records : Displayed in rows within each table. A typical example of a record is data for a specific product (identifier, product name, category) stored in a table called Products. Numerical relationships (Relationships) : Defines a numerical relationship between two entities, such as 1:1, 1:N or M:N. A product can be related to another product according to a specific product category. Cardinality : Refers to the number of entities participating in a relationship. 1:1 (one entity associated with one entity), 1:N (one entity associated with many entities), M:N (many entities associated with many entities) .Primary key : A field or set of fields in a data table that is used to uniquely Telegram Number Data identify each record in a table. Foreign key : Is a field or a set of fields in a data table used to establish a relationship between two tables in the database. elements in the data model A data model consists of many components What is data modeling? Data modeling is the process of visually representing an entire information system or parts of it to communicate the connections between data points and structures. Data models are built based on business needs and goals. Data modeling begins with gathering information about business requirements from stakeholders and end users. These rules are then “translated” to form a specific data structure. In simple terms, a data model is like a building plan that architects create. Types of data models Like any design process, database and information system design is built from overview to detail.
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Data model types can be divided into three main categories corresponding to three levels. The data modeling process begins with a conceptual model , is driven by a logical model , and is encapsulated in a physical model . types of data models Three main types of data models Conceptual Data Model They are also called domain models and provide a bird's-eye view of what's inside the system and what business rules it has. Conceptual models are often created as part of the project requirements gathering process. Conceptual data models focus on describing concepts, entities, and relationships between them in an abstract way.
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