File Name: conceptual logical and physical database design .zip
- Conceptual, Logical and Physical Data Model
- Data model
- Data Modelling: Conceptual, Logical, Physical Data Model Types
This article follows on from Database Design Phase 1: Analysis.
Conceptual, Logical and Physical Data Model
A conceptual schema is a high-level description of informational needs underlying the design of a database. Typically this is a first-cut model, with insufficient detail to build an actual database. This level describes the structure of the whole database for a group of users. The conceptual model is also known as the data model that can be used to describe the conceptual schema when a database system is implemented. A conceptual schema or conceptual data model is a map of concepts and their relationships used for databases. This describes the semantics of an organization and represents a series of assertions about its nature.
The design of a database is generally divided into three phases: Conceptual design. Database design involves classifying data and identifying interrelationships. Exercise 1: electric company An electric company has several plants in various cities. It is often used for communicating ideas and in strategic data projects. The logical data model is consistent and compatible with a specific type of database technology.
This chapter explains how to create a logical design for a data warehousing environment and includes the following topics:. Your organization has decided to build a data warehouse. You have defined the business requirements and agreed upon the scope of your application, and created a conceptual design. Now you need to translate your requirements into a system deliverable. To do so, you create the logical and physical design for the data warehouse. You then define:. The logical design is more conceptual and abstract than the physical design.
There are three different types of data models: conceptual, logical and physical, and each has a specific purpose. But with the different types of data models, an organization benefits from using all three, depending on the information it wishes to convey and the use cases it wants to satisfy. The conceptual data model should be used to organize and define concepts and rules. Typically, business stakeholders and data architects will create such a model to convey what a system contains. In contrast, the logical data models and physical data models are concerned with how such systems should be implemented. Like the conceptual data model, the logical data model is also used by data architects, but also will be used by business analysts, with the purpose of developing a database management system DBMS -agnostic technical map of rules and structures.
Conceptual, logical and physical model are three different ways of modeling Physical ERD represents the actual design blueprint of a relational database.
Data Modelling: Conceptual, Logical, Physical Data Model Types
A data model or datamodel      is an abstract model that organizes elements of data and standardizes how they relate to one another and to the properties of 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. The term data model can refer to two distinct but closely related concepts.
Data modeling data modelling is the process of creating a data model for the data to be stored in a database. This data model is a conceptual representation of Data objects, the associations between different data objects, and the rules. Data modeling helps in the visual representation of data and enforces business rules, regulatory compliances, and government policies on the data. Data Models ensure consistency in naming conventions, default values, semantics, security while ensuring quality of the data. The Data Model is defined as an abstract model that organizes data description, data semantics, and consistency constraints of data.
What is Data Modelling?
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