DBMS Tutorial

DBMS Tutorial

Database Management System or DBMS in short refers to the technology of storing and retrieving users' data with utmost efficiency along with appropriate security measures. This tutorial explains the basics of DBMS such as its architecture, data models, data schema, data independence, E-R model, relation model, relational database design, and storage and file structure and much more.

Why to Learn DBMS?

Traditionally, data was organized in file formats. DBMS was a new concept then, and all the research was done to make it overcome the deficiencies in traditional style of data management. A modern DBMS has the following characteristics −

• Real-world entity − A modern DBMS is more realistic and uses real-world entities to design its architecture. It uses the behavior and attributes too. For example, a school database may use students as an entity and their age as an attribute.

• Relation-based tables − DBMS allows entities and relations among them to form tables. A user can understand the architecture of a database just by looking at the table names.

• Isolation of data and application − A database system is entirely different than its data. A database is an active entity, whereas data is said to be passive, on which the database works and organizes. DBMS also stores metadata, which is data about data, to ease its own process.

• Less redundancy − DBMS follows the rules of normalization, which splits a relation when any of its attributes is having redundancy in values. Normalization is a mathematically rich and scientific process that reduces data redundancy.

• Consistency − Consistency is a state where every relation in a database remains consistent. There exist methods and techniques, which can detect attempt of leaving database in inconsistent state. A DBMS can provide greater consistency as compared to earlier forms of data storing applications like file-processing systems.

• Query Language − DBMS is equipped with query language, which makes it more efficient to retrieve and manipulate data. A user can apply as many and as different filtering options as required to retrieve a set of data. Traditionally it was not possible where file-processing system was used.

DBMS Characteristics

Database is a collection of related data and data is a collection of facts and figures that can be processed to produce information. Mostly data represents recordable facts. Data aids in producing information, which is based on facts. For example, if we have data about marks obtained by all students, we can then conclude about toppers and average marks.

A database management system stores data in such a way that it becomes easier to retrieve, manipulate, and produce information. Following are the important characteristics of DBMS.

• ACID Properties − DBMS follows the concepts of Atomicity, Consistency, Isolation, and Durability (normally shortened as ACID). These concepts are applied on transactions, which manipulate data in a database. ACID properties help the database stay healthy in multi-transactional environments and in case of failure.

• Multiuser and Concurrent Access − DBMS supports multi-user environment and allows them to access and manipulate data in parallel. Though there are restrictions on transactions when users attempt to handle the same data item, but users are always unaware of them.

• Multiple views − DBMS offers multiple views for different users. A user who is in the Sales department will have a different view of database than a person working in the Production department. This feature enables the users to have a concentrate view of the database according to their requirements.

• Security − Features like multiple views offer security to some extent where users are unable to access data of other users and departments. DBMS offers methods to impose constraints while entering data into the database and retrieving the same at a later stage. DBMS offers many different levels of security features, which enables multiple users to have different views with different features.

Who Should Learn DBMS

This DBMS tutorial will especially help computer science graduates in understanding the basic-to-advanced concepts related to Database Management Systems.

Prerequisites to Learn SQL

Before you start proceeding with this tutorial, it is recommended that you have a good understanding of basic computer concepts such as primary memory, secondary memory, and basics of data structures and algorithms.

DBMS Jobs and Opportunities

The modern technologies like big data, cloud computing, and IoT created a high demand for DBMS professionals. Almost every major company is recruiting IT professionals having good experience with DBMS.

Following are the job roles for which you can apply after learning DBMS −

• Database Administrator (DBA)
• Data Analyst
• Database manager
• Data Scientist
• Database Testers
• Cloud Database Expert
• Information Security Analyst
• Data Modeler
• Many more...

So, you could be the next potential employee for any major companies who hires DBMS experts. Start learning DBMS using our simple and effective tutorial anywhere and anytime absolutely at your pace.

Frequently Asked Questions about DBMS

There are numerous Frequently Asked Questions(FAQ) about DBMS, this section tries to answer some of them briefly.

What is the Full Form of DBMS?

The full form of DBMS is Database Management System.

What is Database?

A database can be defined as an organized collection of structured data or information. It can be stored either locally or on a remote server.

What are the components of a DBMS?

Components of a DBMS is listed below −

• Hardware − It refers to the physical machines or devices such as servers and storage systems.

• Software − It is the set of commands or programs that controls the database.

• Data − This is the information stored in database.

• Data Access Language − DBMS requires a language like SQL to interact with the database.

• Users − People who interact with the database are called users. They can be database administrators, developers, and end-users.

What are the ACID properties in DBMS?

Atomicity, Consistency, Isolation, and Durability are known as the ACID properties of DBMS.

What is a database constraint?

Database constraints are some set of rules or conditions that controls behavior of a database table.

What is primary key in DBMS?

A primary key in DBMS is a unique identifier for a record in the specified table. It make sure that each record can be uniquely identified and cannot contain NULL values.

What is a composite key?

A composite key is a type of primary key that consists of two or more columns together to uniquely identify a record in a table.

What is the ER diagram in DBMS?

An ER diagram in DBMS is a visual representation of the database schema. Its full form is Entity Relationship Diagram. It shows the entities, their attributes, and the relationships between them.

What is a database view?

A database view is a virtual table that is created when a query is written using data access language like SQL.

What is a database trigger?

A set of instructions that is automatically executed in response to certain events on a particular table or view is called as database trigger.