This guide to the Structured Query Language (SQL) describes the SQL database language specified by the ANSI/ISO SQL standard and used by many of today's leading database management systems, including DB2, OS/2 E.E., Oracle, Ingres, Sybase, SQL server, SQLBase and dBASE IV. Written for users who are new to databases, as well as for experienced programmers, this text is a straight forward account of what SQL is, why it is important and how to use it. For beginners, there's a step-by-step account of how to use the language. The authors then launch into issues on database structure, the most efficient way to update data, SQL security, programming with SQL and SQL's future directions.