Showing posts with label What is Database Schema?. Show all posts
Showing posts with label What is Database Schema?. Show all posts

Wednesday 3 May 2017

What is Database Schema?

In this post, I will explain what is Database Schema?

Database Schema represents the logical structure of all or part of a relational database. It can exist both as a visual representation and as a set of formulas known as integrity constraints. These formulas are expressed in a data definition language, such as SQL. A Database Schema indicates how the entities that make up the database relate to one another, including tables, views, stored procedures, and more.

Typically, a database designer creates a database schema to help programmers whose software will interact with the database. The process of creating a Database Schema is called data modelling. Conceptual schema focus on an organization’s informational needs rather than the structure of a database.

There are two main kinds of database schema:
1. A logical database schema conveys the logical constraints that apply to the stored data. It may define integrity constraints, views, and tables.
2. A physical database schema lays out how data is stored physically on a storage system in terms of files and indices.

At the most basic level, a Database Schema indicates which tables or relations make up the database, as well as the fields included on each table.