Introduction to SQL

Introduction to SQL


SQL is a standard structured query language for accessing databases.

SQL is just a query language, it is not a database.

If you want To perform or execute any SQL related queries, you need to install any database like Oracle, MySQL, Microsoft SQL Server, and Microsoft Access etc.


What Is SQL?

SQL stands for Structured Query Language and it is pronounced as S-Q-L or sometime See-Qwell.

SQL lets you access and manipulate databases.

SQL is an ANSI (American National Standards Institute) standard.

All RDBMS systems like MySQL, Microsoft Access, Oracle, Sybase, and SQL Server use SQL as standard database language.





What Can SQL do?

SQL can execute queries against a database

SQL can retrieve data from a database

SQL can insert/update/delete records in a database

SQL allows to embed within other languages using SQL modules, libraries & pre-compilers.

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





SQL is a Standard - BUT....

Although SQL is an ANSI (American National Standards Institute) standard, there are different versions of the SQL language.

However, to be compliant with the ANSI standard, they all support at least the major commands (such as SELECT, UPDATE, DELETE, INSERT, WHERE) in a similar manner.

Note: Most of the SQL database programs also have their own proprietary extensions in addition to the SQL standard!