Dummies - SQL AIO Desk Reference For Dummies

Introduction

SQL is the internationally recognized standard language for dealing with data in relational databases. Originally developed by IBM, SQL became an international standard in 1986. The standard was updated in 1989, 1992, 1999, and 2003. It continues to evolve and gain capability. Database vendors continually update their products to incorporate the new features of the ANSI/ISO standard. (ANSI is the American National Standards Institute, and ISO is the International Organization for Standardization.)

SQL is not a general-purpose language, such as C++ or Java. Instead, it is strictly designed to deal with data in relational databases.

With SQL, you can

• Create a database, including all tables and relationships
• Fill database tables with data
• Change the data in database tables
• Delete data from database tables
• Retrieve specific information from database tables
• Grant and revoke access to database tables
• Protect database tables from corruption due to access conflicts or user mistakes