Data Model Meaning
A data model is a set of concepts for describing data, data relationships, data semantics and constraints. It is a collection of conceptual tools for understanding data, relationships among data, data semantics and consistency constraints.
A common misconception is that a data model implies a physical database design. However, data models can be used to describe any type of data structure whether it exists in a database or not. A database however cannot exist without some underlying physical design.
In simple terms, a data model is an abstract model that organizes elements of data and standardizes how they relate to one another and to properties of the real world entities. For instance, a data model may specify that the data element representing a car be composed of a number of other elements which, in turn, represent the color and size of the car and define its owner.
Data models are specified in a data modelling notation, which is often graphical in form.
What are the different types
1. Conceptual model
Describes the semantics of a domain without constraining how those semantics will be implemented in any database.
2. Logical model
Describes the semantics of a domain in an implementation-independent fashion.
3. Physical or database model
Describes how data is stored within a specific database management system.
At the highest level, the conceptual data model is used to define the vocabulary of an application. This vocabulary includes not only the entities involved, but also their properties and relationships. For example, for a social networking site, a conceptual model might capture user profiles and their connections to each other.
In information science, a data model is a systematized arrangement of concepts. A concept is an idea about something (like a person or thing). A concept can be expressed in terms of characteristics (properties) that are shared by many things or beings (instances).
Some examples of data models include:
- Relational model: This model organizes data into tables, also known as relations, with each table consisting of rows (also known as tuples) and columns (also known as attributes). The tables are connected by relationships, which allow data to be queried and accessed in a logical and organized manner.
- Hierarchical model: This model organizes data into a tree-like structure, where each record has a single parent record and zero or more child records. The parent-child relationships allow data to be accessed and queried in a hierarchical manner.
- Network model: This model is similar to the hierarchical model, but allows multiple parent-child relationships, allowing for a more complex and flexible data organization.
- Object-oriented model: This model organizes data into objects, which are logical representations of real-world entities. The objects are associated with data and behaviors, and can be related to each other through relationships.
- Document model: This model organizes data as documents, which can contain both data and metadata (data about the data). The documents can be queried and accessed using a language specifically designed for working with unstructured data.
These are just a few examples of data models; there are many other types of data models that are used in different contexts and for different purposes.