What is SQL? #
- SQL stands for Structured Query Language
- SQL lets you access and manipulate databases
- SQL became a standard of the American National Standards Institute (ANSI) in 1986, and of the International Organization for Standardization (ISO) in 1987
SQL is a database computer language designed for the retrieval and management of data in a relational databases like MySQL, MS Access, SQL Server, MS Access, Oracle, Sybase, Informix, Postgres etc. SQL stands for Structured Query Language. SQL was developed in the 1970s by IBM Computer Scientists.
SQL is not a database management system, but it is a query language which is used to store and retrieve the data from a database or in simple words SQL is a language that communicates with databases.
This SQL tutorial helps you learn SQL in simple and easy steps so that you can start your database programming quickly. It covers most of the important concepts related to SQL for a basic to advanced understanding of SQL and to get a feel of how SQL works.
What Can SQL do? #
- SQL can execute queries against a database
- SQL can retrieve data from a database
- SQL can insert records in a database
- SQL can update records in a database
- SQL can delete records from a database
- SQL can create new databases
- SQL can create new tables in a database
- SQL can create stored procedures in a database
- SQL can create views in a database
- SQL can set permissions on tables, procedures, and views
Why to Learn SQL? #
SQL (Structured Query Language) is a MUST for the students and working professionals to become a great Software Engineer specially when they are working in Software Development Domain. SQL is the most common language used almost in every application software including banking, finance, education, security etc. to store and manipulate data.
SQL is fairly easy to learn, so if you are starting to learn any programming language then it is very much advised that you should also learn SQL and other Database related concepts to become a complete Software Programmer. There are many good reasons which makes SQL as the first choice of any programmer:
SQL is the standard language for any Relational Database System. All the Relational Data Base Management Systems (RDBMS) like MySQL, MS Access, Oracle, Sybase, Informix, Postgres and SQL Server use SQL as their standard database language.
Also, software industry is using different dialects of SQL, such as −
- MS SQL Server using T-SQL,
- Oracle using PL/SQL,
- MS Access version of SQL is called JET SQL (native format) etc.
Applications of SQL #
SQL is one of the most widely used Query Language over the databases. SQL provides following functionality to the database programmers:
- Execute different database queries against a database.
- Define the data in a database and manipulate that data.
- Create data in a relational database management system.
- Access data from the relational database management system.
- Create and drop databases and tables.
- Create and maintain database users.
- Create view, stored procedure, functions in a database.
- Set permissions on tables, procedures and views.
This SQL tutorial is prepared for beginners to help them understand the basic as well as the advanced concepts related to SQL languages. This tutorial will give you enough understanding on the various concepts of SQL along with suitable examples.
Before you start practicing with various types of SQL examples given in this tutorial, I am assuming that you are already aware about what is a Database, especially the basics of RDBMS and associated concepts.