This IBM Redbooks publication describes the High Availability Large Database (HALDB) capability available with IMS. IMS HALDB was introduced with IMS Version 7. It allows IMS databases to grow to almost unlimited sizes while providing increased availability. This book updates IMS Version 7 High Availability Large Database Guide, SG24-5751, as well as adding topics that were not covered in the previous book.

This publication provides a broad explanation of HALDB and its uses. Specific areas covered include:

-HALDB overview, definition, and structure

-Migration from non-HALDB databases

-Application considerations

-HALDB database administration

This publication documents our hands-on experience in a test environment. It includes migration and administration examples. Some IBM Data Management Tools for IMS are also discussed in this publication. Special emphasis is given to the IMS HALDB Conversion and Maintenance Aid product. Examples of the use of these tools are provided.

Part 1. HALDB overview

Chapter 1. HALDB introduction and structure

Chapter 2. Defining HALDB databases

Chapter 3. HALDB and DBRC

Chapter 4. Partition definition utility

Chapter 5. Batch definition of HALDB

Chapter 6. Partition initialization

Chapter 7. Partition selection

Part 2. Migration

Chapter 8. Migration from non-HALDB to HALDB

Chapter 9. Migration examples

Chapter 10. Using the HALDB Conversion and Maintenance Aid

Part 3. Application considerations

Chapter 11. Application considerations

Part 4. Administration

Chapter 12. HALDB online commands

Chapter 13. Backup and recovery

Chapter 14. HALDB reorganization

Chapter 15. Changing existing HALDB databases

Chapter 16. Using IMS tools for HALDB

Part 5. Appendixes

Appendix A. Sample GENJCL.USER skeletons for HALDB allocation

Appendix B. HALDB functions added by APARs

Appendix C. Summary of HALDB utilities