RELATIONAL DATABASE MANAGEMENT SYSTEMS

What is a database ?

A database is an organized collection of interrelated data. 

Data has always been an useful entity, and when it becomes huge, then it becomes an urgency to store it somewhere, so that it can be referred or retrieved whenever required at some later point of time.

In early ages, our predecessors carved on stones for the sake of records, then after the invention of paper, the information was started to be written on paper.

Now in the age of science and technology, we have developed such electronic gadgets, where the procedures of storing data are just a touch away.

So, the proper formatted organization of large amount of data, which we store in memory devices, is referred to as DATABASE.

e.g.

• Banks have to store a huge amount data about its customers and their accounts. So, the data about their Customers is an example of database.
• Airlines ticketing services has store data about its passengers and their bookings. So that data about passengers is an example of database.
• All the email-id providers have to store huge amount of data of their users.So the data of those users forms the database.
• Universities have to store information about their students and their corresponding courses etc. So, all the info related to the students forms the database.
• All the countries keeps the record of its citizens, which also forms the perfect example of database.

What is a Database Management System ?

Database Management System is a set of programs ( i.e. a software ), which helps the user to store and manage data in a very organized way as per the requirements.

Let's say we run a showroom, and we want to store data about every that customer who visits our store, so that we can get to know about our customer base and moreover we can inform customers of special discounts and offers by retrieving their contact numbers from our Customer table stored in the database.

 So, DBMS(i.e. Database Management Systems) help us in creating databases.

A database so created may consists of so many tables, relationships among those tables, indexes, views etc.

Here in the above Scenario, we would like to create a table named Customer, which goes into the database, and then populate that table with the values of customers who visits our store.

The table so created would further consists of attributes, say : name_of_customer, Address, Contact_no, No_of_visits, email_id  etc.

we will insert values of all the customers who visits our store corresponding to the attributes present in the customer table.

  

            Conclusively, DBMS is a software (there are many such DBMS softwares available on the internet, that can be downloaded, such as Oracle database 11g, MySql, Microsoft Sql Server etc. ), which we use to create( using SQL(Structured Query Language)  coding ) databases as per our requirements.

In short, a DBMS allows us to perform :

• Reading operation
• Insertion operation (i.e. inserting values into the tables)
• Modification operation (i.e. changing values or table structures at some later point of time)