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Automatic Rollback

Due to Transaction Failure

Automatic rollback occurs when a transaction fails or an application requests recovery by means of the ROLLBACK command. CA IDMS/DB writes an ABRT checkpoint for the transaction and automatically rolls out the changes made to the database by the transaction. The recovery occurs while the system continues to process requests by other concurrently active transactions.

Note: Automatic rollback also occurs when an error is encountered executing SQL or physical DDL statements. In these cases, an RTSV checkpoint record is written instead of an ABRT checkpoint, but in other respects, the two recovery operations are the same.

Example

The following example shows how an automatic rollback occurs. In this example, transaction B aborts. CA IDMS/DB then performs an automatic rollback for transaction B while other transactions continue to process.