ROLB command

The Rollback (ROLB) command is used to dynamically back out changes and return control to your program. You cannot use this command in a CICS® program.

Format

Read syntax diagramSkip visual syntax diagramEXECDLIROLB

Options

No options are allowed with the ROLB command.

Usage

When a batch or BMP program determines that some of its processing is invalid, two commands make it possible for the program to remove the effects of its inaccurate processing. These are the rollback commands, ROLL and ROLB.

The ROLB command is valid in batch programs when the system log is stored on direct access storage and dynamic backout has been specified through the use of the BKO execution parameter.

Issuing the ROLB causes IMS DB to back out any changes your program has made to the database since its last checkpoint, or since the beginning of the program if your program has not issued a checkpoint. When you issue a ROLB command, IMS DB returns control to your program after backing out the changes, so that your program can continue processing with the next statement after the ROLB command.

Example

EXEC DLI ROLB;
Explanation

This example shows how to dynamically back out changes and return control to your program with the ROLB command.

Restrictions

Restrictions for the ROLB command:

  • You cannot use this command in a CICS program.
  • You must first define an I/O PCB for your program before you can use this command.
  • You cannot reestablish position in the midst of nonunique keys or nonkeyed segments.
  • You cannot use this command when the system log is stored on direct access storage and dynamic backout has not been specified.