eNotes

Unit: 7 Working with database

Database

Why use a database?

Databases make updating data easy and reliable, and they help to ensure accuracy. They offer security features to control access to information, and they help us avoid redundancy. A database is a structure that stores information in an organized, consistent, reliable, and searchable way.

The various reasons a database is important are −

Manages large amounts of data

A database stores and manages a large amount of data on a daily basis. This would not be possible using any other tool such as a spreadsheet as they would simply not work.

Accurate

A database is pretty accurate as it has all sorts of build in constraints, checks etc. This means that the information available in a database is guaranteed to be correct in most cases.

Easy to update data

In a database, it is easy to update data using various Data Manipulation languages (DML) available. One of these languages is SQL.

Security of data

Databases have various methods to ensure security of data. There are user logins required before accessing a database and various access specifiers. These allow only authorised users to access the database.

Data integrity

This is ensured in databases by using various constraints for data. Data integrity in databases makes sure that the data is accurate and consistent in a database.

Easy to search data

It is very easy to access and search data in a database. This is done using Data Query Languages (DQL) which allow searching of any data in the database and performing computations on it.

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