Large Objects with DB2 for z/OS and OS/390

An IBM Redbooks publication


The amount of data to be managed by workstations, middleware systems and mainframes, is growing day by day. The times are changing, and so the requirements for a database management system (DBMS) are changing.
With the incorporation of object-orientation into DB2 for OS/390, you can define new data types and functions. Some of the data objects you want to model may well be very large and complex. The foundation of object-relational extension, introduced with DB2 for OS/390 Version 6 has two major functions. One is based on support for large objects (LOB), and the other is support for user defined functions, user defined distinct types, and triggers. These large objects can contain text documents, images or even movies, and can be stored directly in the DBMS with sizes up to 2 gigabytes per object and 4.000 terabytes per LOB column.
Normally, large objects are used and manipulated through Graphical User Interfaces from a workstation. So with the implementation of LOBs we can exploit the functionalities of the DB2 family and the capacity that DB2 for z/OS provides today. The introduction of these new data types implies some changes in the administration processes and programming techniques.
In this IBM Redbooks publication we describe the new data types, and provide some useful information on how to design and implement LOBs. We also offer examples of their use, programming considerations, and the new processes which are necessary for administration and maintenance.

Table of contents

Chapter 1. Introduction
Chapter 2. Large objects with DB2
Chapter 3. Creating LOBs
Chapter 4. Using LOBs
Chapter 5. DB2 Extenders and LOBs
Chapter 6. Data administration with LOBs
Chapter 7. Performance with LOBs
Appendix A. Sample jobs output
Appendix B. Unicode implementation
Appendix C. Recent maintenance
Appendix D. Additional material


Publish Date
01 July 2002

Last Update
10 November 2004

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