Understanding Database Management Systems

Introduction

Nowadays, data is the new oil. As more and more devices are being used by people to stay connected in this digital world, more and more data is being generated every second by these devices. This data is used to perform analysis to gather insights from them.

But to perform analysis and gather insights from the data, we need to store it somewhere. That is where database management systems come into the picture. The focus of this article is to discuss briefly what database management systems are and their features.

Database Management Systems

Database management systems (DBMS)

Database management systems (DBMS) are software that is used for creating and managing databases. They act as an interface between the database and the end user. With the help of DBMSs, we can perform various tasks on a database, like creating a database, storing data in the database, fetching the data whenever required, and a lot more.

DBMSs are of various types depending on the type of data they deal with. The most popular types are relational and non-relational databases. In relational DBMSs, the data is stored in a tabular format containing rows and columns. Each column represents an attribute, and each row defines a new record. Some of the popular relational DBMSs are SQL Server, IBM DB2, PostgreSQL, and MySQL. Below we have discussed a couple of databases

SQL Server

SQL Server is a popular database management system developed by Microsoft. It was first launched in 1989 and has been growing throughout the years by adding new features. It is mostly used for large-scale enterprise applications. It comes with different variants like Enterprise and Express editions.

What is PostgreSQL?

PostgreSQL is an open-source relational database management system. It started as the POSTGRES project at the University of California back in 1986. It is being developed and maintained by PostgreSQL Global Development Group. It runs on all major operating systems and contains 170 of the 179 mandatory features for SQL:2016 Core Conformance.

Find a detailed article about PostgreSQL here: What Is PostgreSQL?

In non-relational DBMSs or NoSQL DBMSs, we can store vast amounts of data with little to no worry about the structure of the data. It provides schema-free options to store the data. These kinds of database solutions are helpful when the structure of your data changes frequently or you are working with big data. Some of the popular NoSQL solutions are Apache Cassandra, MongoDB, etc.

Why We Need Database Management Systems

DBMSs came into existence to solve the problems developers faced with traditional file management systems. Below listed are a few reasons why we need a DBMS,

Controlling redundancy

Data redundancy was a big problem in traditional file-based systems. Data redundancy refers to the duplication of data at one or more places.

For example, consider a situation where you have two tables: customer details and customer orders. Every time a customer registers in your application, you create a new record in the customer details table, which includes the customer's address. Likewise, every time this new customer places an order, you store this order as a new record in the customer orders table where you store the customer's address again.

Here, the customer’s address is repeated in both tables, which creates redundancy. With the help of normalization, we can reduce redundancies in a DBMS.

Restricting unauthorized access

While working with large databases, many users will access the database, but everyone should not be able to perform all the operations on this database. If they do, that poses a security threat.

For example, consider a scenario in which you are working with a financial database. You don’t want all users to be able to create, update, or delete records in any of the tables or delete databases. This would have a catastrophic impact.

With a DBMS, you can control what kind of operations a user of a particular role can perform on a database.

Providing backup and recovery

One of the key features of a DBMS is its ability to perform backup and recovery operations. A DBMS contains a backup and recovery subsystem that handles the recovery of the database to the previous stable state.

Consider a scenario where a complex transaction or operation was running on your database, but due to some hardware failure, your computer crashed. In such cases, the backup and recovery subsystem of the database ensures that our database reaches the state it was in before the transaction or operation had begun.

Enforcing integrity constraints

Integrity constraints are one of the key features of most DBMSs. With integrity constraints, a DBMS provides us with a mechanism to define our own enforced constraints for the data stored in our database and implement them. Integrity constraints can be as simple as defining a constraint to accept the values of a particular data type or anything more complex.

Consider you have a students’ database and a student_info table where you store all the student information. This table has various columns, like firstname, lastname, rollNo, to name a few. Now you don't want to have to manually make sure that none of the records contain the rollNo or firstname as null. So, you enforce a NOT NULL constraint to make sure that the table does not accept any records with null for the columns you have defined.

Conclusion

Database management systems have proven to be effective tools for managing and working with databases. They provide an excellent mechanism to work with the data stored inside our database while ensuring the sanity of our data. They also tackle the issue of data redundancy and authorization.

In this article, we have discussed the various ways a DBMS is an ideal solution for dealing with big data and analyzing it to improve customer satisfaction.

There are many types of databases depending on your need. To learn more about types of DBMS, please visit Types of Database Management Systems here.