Commitment control

 

Commitment control is a function that ensures data integrity. It defines and processes a group of changes to resources, such as database files or tables, as a transaction.

Commitment control ensures that either the entire group of individual changes occur on all systems that participate or that none of the changes occur. IBM^® DB2 Universal Database™ for iSeries™ uses the commitment control function to commit and rollback database transactions that are running with an isolation level other than *NONE (No Commit).

You can use commitment control to design an application so that the system can restart the application if a job, an activation group within a job, or the system ends abnormally. With commitment control, you can have assurance that when the application starts again, no partial updates are in the database due to incomplete transactions from a prior failure.

By using the code examples, you agree to the terms of the Code license and disclaimer information.

• What's new for V5R4
  This topic highlights the changes made to this topic collection for V5R4.

• Printable PDF
  Use this to view and print a PDF of this information.

• Commitment control concepts
  These commitment control concepts help you understand how commitment control works, how it interacts with your system, and how it interacts with other systems in your network.

• Starting commitment control
  To start commitment control, use the Start Commitment Control (STRCMTCTL) Command.

• Ending commitment control
  The End Commitment Control (ENDCMTCTL) command ends commitment control for either the job-level or activation-group-level commitment definition.

• System-initiated end of commitment control
  The system can end commitment control, or perform an implicit commit or rollback operation. Sometimes the system-initiated end of commitment control is normal. Other times, commitment control ends with an abnormal system or job end.

• Managing transactions and commitment control
  By using these instructions, you can manage a system with commitment control.

• Scenarios and examples: Commitment control
  These scenarios and examples show how one company sets up commitment control. Code examples for programs that use commitment control are also included in this topic collection.

• Troubleshooting transactions and commitment control
  This information might help you troubleshoot commitment control errors, detect deadlocks, recover transactions after communications failure, know when to force commit and rollback operations, and when to cancel resynchronization and end long-running rollbacks.

• Related information for commitment control
  Listed here are the product manuals and IBM Redbooks™ (in PDF format), Web sites, and information center topics that relate to the commitment control topic. You can view or print any of the PDFs.