• Kalpesh Agrawal

What is SQL

SQL(Structured Query Language) is a special-purpose database computer language designed to manage the data held in a Relational database management system (RDBMS).

Data is the Oil of the 21st century, and SQL is one of the most popular programming languages to manage the data, that is the reason why most companies require SQL knowledge while hiring candidates.

SQL contains 3 major sub-languages:

  1. Data Definition Language(DDL): to create and modify the structure of the database;

  2. Data Manipulation Language(DML): to Read, Insert, Update, and Delete operations on the data of the database;

  3. Data Control Language(DCL): To control the access of the important data stored in the database.

History of SQL

Edgar F. Codd was a Computer Scientist, While working for IBM he invented the relational model for database management. SQL was one of the first commercial languages to utilize this model.

SQL was not entirely adhered to the relational model as described by Codd, it becomes very popular and most used database language.

SQL becomes a standard of the American National Standards Institute (ANSI) in 1986 and becomes a standard of the International Organization for Standardization (ISO).

Originally SQL was developed by Donald D. Chamberlin and Raymond F. Boyce based on the relational model developed by Edgar. F. Codd.

Uses of SQL

Let's see the uses of SQL and the operations we can perform related to the database.

  • You can create and drop tables and databases using SQL.

  • You can insert and update the tables and databases using SQL.

  • You can retrieve the data from databases using SQL.

  • You can access the data stored in the RDBMS (Relational Databases Management System).

  • You can set permissions to access the data and on tables, Procedures, and Views using SQL.

  • You can create a whole model using SQL.

  • SQL is supporting websites that are data-driven like Online banking, E-commerce sites, Flight bookings, Social media websites, etc.