Discovering SQL: A Hands-On Guide for Beginners

SUMMARY

We produce and consume ever-increasing amounts of information, and database management systems were created to help us cope with the informational deluge.

Database management systems (DBMSs) accumulate and manage data in various forms, text, images, and sounds, both structured and unstructured. The underlying format for all electronically stored data is digital. DBMSs built upon the relational model are called RDBMS (Relational Database Management Systems).

The RDBMSs manage both data and access to it, applying security policies, and auditing activity. There is a multitude of databases on the market, from desktop to enterprise class servers, from proprietary to open source. A variety of factors must be considered for each RDBMS package deployment: storage capacity, scalability, security, and costs, to name a few. The most popular enterprise class RDBMS packages include Oracle, IBM DB2, and Microsoft SQL Server; the popular open source contenders are PostgreSQL and MySQL; desktop databases are represented by Microsoft Access and OpenOffice embedded HSQLDB.

The Structured Query Language (SQL) is lingua franca of the relational database management systems (RDBMSs) and has roots in IBM research conducted in the late 1960s. The first attempt to standardize SQL was by the American National Standards Institute (ANSI) in 1986, and the current standard is SQL:2008, endorsed by the International Standards Organization (ISO). Despite the published standard, virtually every RDBMS supports ...