Oracle - Introduction

Introduction

The purpose of this module is to teach you about databases, in particular databases based on the relational model. The relational model is widely used in industry and many vendors provide relational products. Oracle, Microsoft Access and Visual FoxPro are three such products. SQL (Structure Query Language) is regarded as being the de facto query language for relational databases and this module uses Oracle as a vehicle for teaching SQL.

SQL is subject to a number of standards: ANSI X3.135 - 1989; SQL2 (or SQL92) and SQL3 (SQL99) and recently SQL4 (2003). The current version of Oracle (version 12c) supports most of the SQL92 standard. It does also offer some support for objects, which is in the SQL99

As you get more familiar with the product, you will come to realise that a lot of the commands detailed in this booklet could have been more easily entered/executed using the power tools. The purpose of the module is to teach you SQL which is standard across many relational products, e.g., Sysbase, Ingres, DB2. The Oracle Developer tools however are proprietary and every product has different tools. The commands in this booklet however can be executed on most relational platforms with little amendment; this would not be true if the toolset were used.