From Hard-Disk To AWS How DBMS Became a Vital Component Of Industry
To understand the Database Management System (DBMS), we must first know what data and information are and finally, how the database is formed. So in computer science terms, the raw and isolated facts about an entity are called data e.g., Text, Audio, Image Video, etc. and similarly processed and meaningful usable data is called information. Now you may be confused about what to call data and what to call information, as both terms are pretty close to each other. Let’s consider there’s an exam going on of two students, as the first student is good at studies and preparation for the exam, the paper was too easy for him and he was able to write properly. But the second student was just wasting his time playing video games a day before the exam, he didn’t get time to prepare and was struggling in the exam. Now he tries to copy from the first student who was sitting next to him, he was able to copy some of the answers that the first student was writing till the teacher caught him and snatched his answer sheet. Karma doesn’t spare anyone. Anyway, for him all the answers that the first student had written in his answer sheet were data and the answers that he copied and written in his answer sheet were information. Similarly, if we talk about the first student, then for him the books that he used for reference was data, and the points or answers that he wrote in the exam was information. So now, what is a database? It is a collection of similar or related data is called a database e.g., video is an example of data but YouTube is an example of a database.
From the above points, we can say DBMS is a software or tool used to create, manipulate, or delete the database. e.g., Oracle, IBM. With a primary goal to provide an efficient and convenient way of storing and retrieving data properly. It is widely used software in different industries like banking, railway, and the university where we have to deal with lots of data and information. It is specially designed to handle the vast amount of data and may extend up to terabytes.
The important developments in the database system started in the late 1950s, where magnetic tapes were used to record and read data. Mostly this system or application had a hierarchy structure that mainly used a network system. This system was very accurate while dealing with the original query, but when a new query was used, it was unable to handle it. Then in the 1960s, hard disks were introduced due to which it was faster to retrieve data and it was not required to store data sequentially. A very important development in database management system took place in the year 1970, when Edgar Codd, father of the relational database model, wrote the paper ‘A Relational Model of Data for Large Shared Data Banks’ that led to the formation of SQL query language (one of the most used query language in all over the world). In the 1990s, the World Wide Web was introduced that led to the connection of data with servers that can be accessed anywhere in the world. More recently there has been a growing trend in NoSQL that uses a classical database and does not rely on the rational method.
Before DBMS we mostly relied on the file system for storing and accessing data, but as time went by and data size became larger and larger, the file system was ineffective. As there were a lot of problems like data redundancy, data inconsistency, difficulty in accessing data, atomicity problems, integrity problems, and security problems were all solved by using DBMS.
The main advantage of using DBMS is its atomicity. For example, if you are implementing your database and let’s say there is some problem at the 82nd line in the 100 lines of code. Unlike the operating system, where the code will execute till the 81st line and then an error will be displayed, in DBMS it will not execute at all. That means either it will execute completely or it will not execute at all, due to which large security and data problems can be solved.
In DBMS the data is separated into two files, OLAP (Online Analytical Processing) and OLTP (Online Transaction Processing). In OLAP the historical data is stored, which is subject-oriented and is used for decision making. Here, the data file size can be in terabytes and is available in reading format only. Whereas in OLTP, current data is application-oriented and used for day-to-day operations. Here, the data file size can be in MBs or GBs and is available in reading and writing format. e.g., if we talk about Indian Railways, from 1950 passengers’ and employees’ data is available which is stored in an OLAP file and the current data is stored in an OLTP file. The main reason behind doing this is to reduce the data size so that it can be accessed easily and with less processing time. Moreover, the data stored in the OLAP file can be used for the experience because with the help of that data, railways can find out information like on which route more passengers travel so that a schedule can be prepared in advance.
Let’s see how DBMS works. Firstly, all the information related to the database is collected from the user which is called an SRS model. Then from it, ER(Entity Relationship) diagram is prepared for a proper understanding of all data. If it consists of entity sets, attributes, degree. Mapping is done between all attributes. Then all the data is converted into the Relation model that consists of the table. After that, normalization is done on the data to get a proper output table that will cover all relations between attributes. Most importantly, due to normalization, data redundancy is reduced due to which data becomes consistent. After normalization, the query language is used so that the tabular form of the data can be converted into code, for this, we mostly use SQL Query language. Now the code is saved with the help of the file structure. It can be saved in sorted files as well as in unsorted files depending on the user, also indexing can be done on files so that the processing speed is improved. Once all this is done, then the last and important step of the transaction takes place, where the code is tested and atomicity is checked. Based on this, scheduling is done with some standard protocols as well as with own protocols like timestamp and locking technique to solve the problem of consistency.
Today, DBMS is widely used in almost every field because of its efficiency and consistency in storing and retrieving data properly. With the help of DBMS now companies are getting more and more information from their work and can keep records of it. It’s faster to search for any product information and be more effective in their work. Some of the main applications of DBMS are in sectors like Railways, Banking, Education, Telecommunication, Military, Finance, E-commerce, Airline Reservation Systems, Social Media sites, and the list goes on. Since DataBase Management System is widely used by companies and management it is highly unlikely that it will get replaced in the future and with time more and more improvements would be on their way. Currently, we are storing data in the form of tables which is used since the 1950s. As we moved forward, we improved the way we store data by normalizing it and a similar approach can be expected in the future.
