What Is DB2 Universal Database?

DB2 Universal Database is a Web-enabled relational database management system that supports data warehousing and transaction processing. It can be scaled from hand-held computers to single processors to clusters of computers and is multimedia-capable with image, audio, video, and text support.

DB2 is optimized for each platform to maximize performance. Internally, the DB2 products that run on the mainframe platforms (MVS, z/OS, iSeries, and so on) differ from the products that run on distributed platforms (Linux, Unix, and Windows). The DB2 products for the distributed platforms share the same source code.

DB2 Database Features

The major components of the DB2 Universal Database relational database management system include the database engine and facilities to access data such as the Command Center, Command Line Processor, the Control Center, and application interfaces. A rich suite of tools also is available for the DB2 environment.

The database engine provides the base functions of the DB2 relational database management system. It manages the data, controls all access to it, generates packages, generates optimized paths, provides transaction management, ensures data integrity and data protection, and provides concurrency control. All data access takes place through the SQL interface. The basic elements of a database engine are database objects, system catalogs, directories, and configuration files. 

The basic elements used by DB2 Universal Database include database objects, data integrity, object relational capabilities, system catalog tables, instances, directories, storage objects, configuration files, and recovery objects.

DB2 provides unique constraints to ensure that the values in a set of columns are unique and not null for all rows in the table. Referential constraints let you define relationships between and within tables by requiring that all values of a given column of a table also exist in some other table or column. Check constraints are provided to enforce rules not covered by uniqueness or referential integrity. Check constraints allow you to specify a range of values allowed in one or more columns of every row of a table.

DB2's Various Flavors

DB2 comes in the following editions: DB2 Express, DB2 Workgroup Server Edition, DB2 Enterprise Server Edition, and DB2 Personal Edition. All four editions provide the same full-function database management system, but they differ from each other in terms of connectivity options, licensing agreements, and additional function.

To access data stored on mainframe computers, DB2 Connect is available in the following editions: DB2 Connect Enterprise Edition and DB2 Connect Personal Edition. For developers, the following editions are available: DB2 Universal Developer's Edition and DB2 Personal Developer's Edition. The products include DB2 plus a wide range of development tools.

DB2 Workgroup Server Edition

DB2 Workgroup Server Edition is licensed on a per-user basis. It's available for the AIX, HP-UX, Linux, Solaris, Windows Server 2003, Windows 2000, Windows XP, and Windows NT platforms.
The DB2 Workgroup Server Edition is ideal for smaller departmental applications or for applications that do not need access to remote databases on iSeries or zSeries.

DB2 Enterprise Server Edition

DB2 Enterprise Server Edition includes all the features provided in the DB2 Workgroup Server Edition, plus support for host connectivity, providing users with access to DB2 databases residing on iSeries or zSeries platforms. DB2 Enterprise Server Edition is available for the AIX, HP-UX, Linux, Solaris, and Windows platforms.
For very large databases, complex workloads, or increased parallelism, the DB2 Database Partitioning Feature (DPF) is available for the DB2 UDB Enterprise Server Edition. The DPF is ideal to handle the large amounts of data required for biotechnology and mapping genetic codes. This feature allows databases to be partitioned across multiple independent computers of a common platform. To end users and application developers, it still appears as a single database on a single computer.

DB2 Express Edition

DB2 Express Edition is the same full-function DB2 database as DB2 Workgroup Server Edition, but new features make it easy to transparently install within an application. DB2 Express Edition is available for the Linux and Windows platforms.

DB2 Personal Edition

DB2 UDB Personal Edition allows you to create and use local databases and access remote databases if they're available. DB2 Personal Edition is available for the Linux and Windows platforms.

DB2 Personal Developer's Edition

DB2 Personal Developer's Edition includes DB2 Universal Database Personal Edition, DB2 Connect Personal Edition, and DB2 Software Developer's Kits for Windows platforms.

The DB2 Personal Developer's Edition allows a developer to design and build single-user desktop applications. It provides all the tools needed to create multimedia database applications that can run on Linux and Windows platforms and can connect to any DB2 server. The kit includes Windows and Linux versions of DB2 Personal Edition plus all the DB2 Extenders.

DB2 Universal Developer's Edition

DB2 Universal Developer's Edition includes the full suite of DB2 products, including all DB2 server editions, DB2 Connect, the DB2 Extenders, Warehouse Manager, and Intelligent Miner, and application development tools for all supported platforms.

This kit gives you all the tools you need to create multimedia database applications that can run on any of the DB2 client or server platforms and can connect to any DB2 server. It includes the following complementary products: DB2 Everyplace Software Development Kit, WebSphere Application Server, WebSphere Studio Site Developer Advanced, WebSphere MQ and QMF for Windows.

DB2 Connect Enterprise Edition

DB2 Connect Enterprise Edition provides access from network clients to DB2 databases residing on iSeries or zSeries host systems. DB2 Connect Enterprise Edition is available for AIX, HP-UX, Solaris, Linux, and Windows platforms.

DB2 Connect Personal Edition

DB2 Connect Personal Edition provides access from a desktop computer to DB2 databases residing on IBM iSeries or IBM zSeries host systems. DB2 Connect Personal Edition is available for the Linux and Windows platforms.

The server edition of DB2 Universal Database Version 8 runs on AIX, Linux, HP-UX, Solaris, and Windows platforms. The client edition of DB2 runs on the same platforms as the server. The personal edition of DB2 runs on Linux and Windows platforms.