What SQL is and what it does

Summary

SQL (Structured Query Language) is a standard language used to access and manipulate databases. It enables you to run queries to retrieve data and to perform common data operations such as inserting, updating, and deleting records. SQL can also create and manage database structures, including creating databases and tables, defining views, and setting permissions. Although SQL is standardized by ANSI (1986) and ISO (1987), different database systems may implement SQL with proprietary extensions. To use SQL effectively in web development, you typically combine an RDBMS (Relational Database Management System) such as MySQL, SQL Server, or MS Access with server-side scripting (e.g., PHP or ASP) and use SQL to fetch the data that your web page displays. RDBMS stores data in tables made up of columns (vertical fields) and rows/records (individual entries).

Key Points

• 1

  SQL stands for Structured Query Language and is used to access and manipulate databases.

• 2

  SQL can retrieve, insert, update, and delete data, and can also create/manage databases, tables, views, and permissions.

• 3

  SQL is ANSI/ISO standardized, but different database systems may add proprietary extensions; RDBMS stores data in tables with columns and rows.