In this blog post, we will learn how a DBMS maintains consistency and security of information and what role it plays in modern society.
The 21st century is truly a flood of information, with so much information available to us. This was made possible by the rapid development of the Internet and computers. These changes have had a significant impact not only on individual lifestyles but also on the overall structure of society. As access to information has improved, people have become better at obtaining more data quickly and making decisions based on that data. However, in the midst of this flood of information, it is important to manage accurate and reliable data. To do this, we need a system to organize and continuously manage data. To this end, a database management system (DBMS) exists. This DBMS is used in many places.
The important things to consider in a DBMS are database consistency and safety. Consistency is the consistency of data, meaning that even if the database is read and written many times, the database does not contain strange values but only appropriate values. Let’s take one example.
Let’s say that a bank processes the deposit and withdrawal details manually. The management details are recorded in a single ledger. At this point, let’s say there was $1 billion in the bank. If two bank employees check the balance at the same time, one withdraws $700 million and the other withdraws $500 million. In this case, the bank only has $1 billion in money, but the two bankers are lending a total of $1.2 billion. This kind of situation occurs because the database for withdrawal history is not properly managed.
As shown above, while one person reads and changes a value in a database, the other person must wait to be able to write the appropriate value. If one person reads $1 billion and covers the ledger so that others cannot read it, the other banker will have to wait for the banker who read it to finish his work. And after the work is finished and the balance is rewritten, the waiting banker will read the new balance and process it. In this case, the banker will not be able to lend $500 million when $700 million is left after lending $300 million.
The importance of DBMS can also be seen in various industries. For example, DBMS also plays an important role in managing patient records in the medical field. Only by consistently managing patient medical records, prescription history, test results, etc. can appropriate medical services be provided. If the database loses consistency, it can have a serious impact on patient treatment. Therefore, it is very important to maintain the consistency and safety of the database in the medical field as well.
The second example is safety. This means that the data must be properly retained and not lost. If the data is lost during multiple readings and writing, it must not be lost. Let’s take another example.
A customer wants to borrow $100 million. At this time, let’s say the customer is so busy that he is about to receive another customer who wants to deposit $200 million. The bank clerk was handling these two customers at the same time and recording the transactions in the ledger. However, he only wrote the ledger for the $100 million loan and failed to write the $200 million deposit. In this case, the $200 million should have gone into the account of the person who wanted to deposit the $200 million, but this money disappeared from the ledger. This is also caused by the failure to manage the database correctly.
As such, making a DBMS efficient requires a lot of thought. When actually creating a DBMS, there are many more points to consider in addition to the two above. As the number of points to consider increases, the system itself may become slower. It is also necessary to have the ability to quickly recover from a machine error that has stopped the system. The purpose of a DBMS is to take into account these many things and to process a large amount of data safely and within the desired time.
In fact, DBMS is used to manage a large number of databases. Although we have only talked about a single bank above, DBMS can be used to manage the deposit and withdrawal history of banks across the country. It can also be used to manage various documents and project-related files within a company. Such a system is also used in educational institutions to efficiently manage students’ grades, attendance, and academic records. In addition, large retailers use DBMS to manage inventory and customer information for more efficient operations. The demand for this will continue to grow. In response to this demand, lighter and more secure DBMSs will continue to be created.
