What is SQL? How SQL is used in the real time?

 

 

What is SQL?

SQL is an abbreviation for structured query language. which also goes by the name sequel even today. it's a language used by the database domain. SQL can be used only for relational type database and not for the others. Relational database is a database which has a tabular method of storing data usually it consists of rows and columns. SQL is a core of relational database which is used for accessing and managing the database with the help of SQL statements you can add columns, update, delete rows of data. We can also retrieve information modify database and perform many more actions. The different subsets of SQL commands are as follows. 

·         DDL- Data Definition Language: it simply deals with the description of the database schema and used to create and modify the structure of database objects in the database. it allows you to perform various operation on the database such as create alter and delete objects. DDL is very popular and extensively used when compared to other commands.

·         DCL- Data Control Language: It allows you to control access to the database grant or revoke other DCL commands. Grant gives user access privileges to the database while revoke withdraws user access privileges given to the user with the help of grant command.

·         TML- Data Manipulation Language: It allows you to access and manipulate data .it helps you to insert, update, delete and retrieve data from the database. so, what does each of this command do, so the insert command is used to insert data into the table. well update is used to update existing data within the table and a truss delete is used to delete records from the database.

·         TCL-Transaction Control Language: It allows you to deal with the transaction of the database. Few of the TCL commands are commit, roll back, save point and transaction. 

So, these were the SQL commands to understand SQL.Let's use an analogy, if two people won't communicate with each other then they have to use a language that is understood by both of them. Here, John wants to start a conversation with Dave and he uses English language to start his conversation. This language is known to Dave as well .so they will continue their conversation but what if one of them didn't understand what the other person spoke there won't be any conversation at all. Relating this analogy if we consider these two people one as user and the other as database. Then that language which is used to communicate between these two is called SQL similarly how a language has the grammar and various rule on how it should be used even the SQL has its own directives.

 We need to know below session for SQL.

1.       Evolution of SQL

2.       Traditional file system.

3.       Advantages of SQL.

 

1.Evolution of SQL: SQL was developed at IBM by Donald Lee Chamberlin and Raymond F boys in the early 1970s. it was initially called as sequel that is structured English query language. but later it was chained to SQL because sequel was a trademark of UK-based engineering company. In the year 1986 American National Standards Institute that is ANSI and the international standards organization that this ISO have deemed the SQL language as a standard language in relational database communication. This is how SQL evolved. since we have understood the evolution of SQL. People from technical background may find the silly but for a beginner it is really important to understand each and every aspect of this topic.

 

2.Traditional file System: In today's computing world managing data is a huge task for our convenience we store the data on documents in different location and this is called file system. without a file system information place in the storage medium would be one large body of data we won't be able to tell where information stops and where it begins. let's look at the formal definition, file system is one which controls how the data is stored and retrieved, it is nothing but information stored in different computer files. Usually while storing a small amount of data the file system is effective. But when it comes to storing the enormous amount of data the file system fails. Let’s look at some of the problems of file system,

·         Data redundancy: when we store similar data in different location of a computer data gets duplicated and this will lead to data redundancy. This will increase the storage size and also leads to failure of security features. Because of this the file system is highly vulnerable in nature. Data redundancy will cause the user not only in terms of security but also economically.

·         limited data sharing and lack of security: data sharing and security are closely related. Sharing data among multiple uses introduces a lot of security risk. In terms of spreadsheet data and other documents the inbuilt file system programs provides only the basic security option. But they are not used most of the time because of this negligence we might face some bigger problems in the near future.

·         Difficulty of getting quick answers: this is one of the major problems in file system because. File system doesn't allow multiple users to access the same data at a given point of time. This means that multiple uses a different work location cannot access the same data simultaneously. this will limit the access to important data if multiple users search for the same data at a given point of time.

·         Data dependence: in the file system files and records are described by a specific physical format that is coded into the application by the programmers. if the format of any one record was changed then we need to make sure that all the remaining records format is updated. This information has to be updated in the system also. Any changes install a structure or access methods could greatly affect the process this might result in failure of that particular application. So, these were few problems that were faced using the file system and the solution for this is SQL and database.

 

 

3.Advantages of SQL: Here are some advantages for SQL. 

·         Well-defined standards: As it says, developers of SQL have clearly mentioned how exactly each and every query has to be written. There is no room for ambiguity when it comes to writing the query the standards have to be followed.

·         Easy to learn: SQL is a language that is used to work with the database. since SQL has a large user base as well as well-defined standard for a beginner it is really easy to learn.

·         Multiple views: This is one of the unique and early features that SQL came up with. View is nothing but creating a virtual table. A virtual table is a temporary table for certain use by doing this we can protect the integrity of the data. SQL has the ability to not only create a single view but can create multiple views.

·         Portable Queries: In nature it means we can execute the SQL query in one system and execute the same query in another system without changing the format. But the condition is that, the environment set up of these two systems has to be same else the query won't be executed.

·         Interactive: The main purpose of SQL is to communicate with the database. we can write complex queries to fit the results from the database and these queries can be easily understood by anyone.

 

How SQL is used in the real time?

SQL in real time since SQL is a language that is used to operate on the database, we need to look at the bigger picture of the data management industry. Here, if I say database it includes SQL language as well. The database is used in different verticals like online stores, health care providers, libraries, financial industry, retail industry, government agencies and many more. Now let's consider some real time examples of the use of SQL and database.

      1.       Education Sector

2.       Health-care Sector

3.      Retail Industry

4.      Financial Sector

 1.Education Sector: Database systems are frequently used in schools’ colleges and universities to store and retrieve the data. This data may be regarding student staff details, course detail, exam details, attendance details and fees details. There’s a lot of interrelated data that needs to be stored and retrieved efficiently to understand. The magnitude of impact that the database has made in this field try to imagine the days when the results were only declared on the school notice board. isn't it easier now to access your exam results with just one click who wouldn't say no to such a drastic change also nowadays the online exams have increased significantly? This has increased the speed of assessment when compared to the olden days all these are possible because of SQL and database technology.

2.Health-care Sector: There were days when people used to stand in front of the clinics and hospitals to get an appointment with a doctor but now the time has changed. In hospitals and medical institution maintaining data related to doctors, patients and staff is a huge task. Effectively coordinating among these three has to be handled seamlessly. With the help of SQL and database this industry has gained a lot with the introduction of SQL and database inventory management has been affected.

3.Retail Industry: Every year leading e-commerce Giants come up with great offers discounts based on your personalized shopping to come up with all this they use database and other technology. The industry utilizes the database and SQL technology extensively and retail industry customers data has to be managed effectively. There’s no scope of error when it comes to handling the data with instigation of SQL and database system. The retail industry cannot only secure the data but also can get the real-time analysis which in turn helps him to make a lot of profit.

 4.Financial Sector: When we speak about this sector it's really hard to even imagine what goes behind the scene. only the experts know how much data will be processed every second managing money, assets, etc. In a real-time is a tedious task .SQL and database technology is helping the financial sector to achieve its primary tasks .SQL queries can be also used to check the fraudulent activities. Looking at the issues of fraudulent activity effective fraud detection requires a financial organization to process a huge amount of customer purchasing data. so, these organizations have to store and retrieve data effectively without causing any burden on another branch of the same organization.

These are the few sectors and industries where the SQL is used in day-to-day transaction. This brings us to the end of this session I hope you are clearly understood what is SQL its evolution and its application. if you have any queries or doubts regarding this session please let me know in the comment section.