An Apache Derby database is an organized collection of objects. Each database has its own system catalog, log files, security, and tuning parameters. SQL is used throughout the database industry as a common method of issuing database queries. Before we examine the SQL language, we need to understand some Apache Derby terminology. We will be referring to the basic components or objects that are defined for each Apache Derby database. These objects include:
The following sections give a brief overview of each object and describe how it is used.
A table is an unordered set of rows. Rows consist of columns. Each column is based on a data type. Tables, once created and populated ...