How do DBMSs ensure the consistency and safety of information in the modern world?

DBMSs play an important role in maintaining the consistency and safety of information to efficiently manage data and prevent data loss and errors in banking, healthcare, education, retail, and more.

 

The 21st century is truly an information deluge, with tons of information available to us. This has been made possible by the rapid development of the internet and computers. These changes have had a huge impact not only on the way individuals live, but also on the overall structure of society. The increased accessibility of information has given people the ability to quickly obtain more data and make decisions based on it. However, amidst this flood of information, it’s important to manage accurate and reliable data. To do this, you need a system to organize and continuously manage it. This is where database management systems (DBMS) come into play. These DBMSs are used in many different places.
The most important thing to consider in a DBMS is the consistency and safety of the database. Consistency is the consistency of the data, so that no matter how many times you read or write to the database, the database will contain the correct values and not strange values. Here’s an example.
Imagine a bank that manually processes deposits and withdrawals. The bank keeps a single ledger. At one point in time, there is $1 billion in the bank. If two tellers check the balance at the same time, one withdraws $700 million and the other withdraws $500 million. At this point, the bank only has $1 billion in the bank, but the two bankers have lent out a total of $1.2 billion. This happens because the database of withdrawals is not properly maintained.
As shown above, one person reads and changes the database while the other waits to write the right value. If one person reads in a billion dollars and covers the books so that no one else can read them, the other banker will have to wait until the previous banker is done. Then, at the end of the day, after the balance has been rewritten, the waiting teller will read and process the new balance. In the example above, the bank would not be able to lend out $500 million with $300 million left over after lending out $700 million.
The importance of DBMSs can be seen in other industries as well. For example, in healthcare, DBMSs play an important role in managing patient records. Patients’ medical records, prescriptions, test results, etc. need to be consistent in order to provide proper medical care. If the database is inconsistent, it can seriously affect the patient’s treatment. Therefore, it is very important to keep databases consistent and secure in the medical field.
The second example is safety. This means that the data should remain intact and not disappear. You don’t want to lose data during multiple reads and writes. Here’s an example.
A customer wants to borrow $100 million. The banker is busy and receives another customer who wants to deposit $200 million. The banker is dealing with both of these customers at the same time, recording each of them in the ledger, but only for the $100 million loan and not for the $200 million deposit. Obviously, the $200 million should be in the bank account of the person who wants to deposit the $200 million, but the money is gone from the record. This is also a result of not managing the database correctly.
As you can see, it takes a lot of thought to make a DBMS efficient. There are many other things to consider when creating an actual DBMS. With so many things to consider, there is a possibility that the system itself will be slow. You also need to be able to recover quickly if the machine crashes. The purpose of a DBMS is to take all of these things into account and process tons of data safely and in a timely manner.
In fact, DBMSs are used to manage a lot of databases. In the above example, we’re talking about a single bank, but a DBMS can be used to manage deposits and withdrawals for banks across the country. It could also be used to manage multiple documents or project-related files within a company. These systems are also utilized by educational institutions to efficiently manage student grades, attendance, academic records, and more. Large retailers also use DBMSs for inventory management and customer information management to enable more efficient operations. These are just a few of the many uses that will continue to grow in demand. To keep up with this demand, lighter-weight and more secure DBMSs will continue to be created.