The iSeries/AS400 contains a relational database called DB2.
DB2 is integrated into the iSeries/AS400 partly above the Machine Interface (MI) and partly in the Licensed Internal Code (LIC). Conventional databases are separate software components that reside on top of the operating system. Since DB2 is integrated throughout the entire system it can achieve a higher level of efficiency because it is tightly integrated with the components with which it communicates. The database management system (DBMS) is a framework for storing and retrieving data. A DBMS must have an interface so users can access and manipulate the data. There are two interfaces to the iSeries/AS400: The Data Description Specifications (DDS) and Structured Query Language (SQL). The DDS, or the native interface, was carried over from the IBM System/38. It has a look and feel similar to IBM’s Information Management System (IMS). The second interface is SQL. This is the industry standard for relational databases.
The inFORM Decisions iDocs product interfaces with the DB2 database and can create custom AS400 reports and produce AS400 spread sheets from this stored data.