Skip to content

About Impact Analysis

Impact analysis is a ChangeMan ZMF facility that shows relationships and dependencies among baseline library components. By querying impact analysis data for selected components you can do the following:

  • Assess the effort involved in completing an intended change. That is, you can find out what and how many other components will be affected if you change a selected component.

  • Avoid product failures that occur when you install a change without considering related components.

Relationships in Impact Analysis Data

Impact analysis lets you evaluate the effect of changing a particular component. A superior component is defined as one that references one or more subordinate components. Likewise, a subordinate component is defined as a component that is referenced by one or more superior components.

The following diagram shows the relationship between superior and subordinate components in impact analysis.

Impact Analysis

Potentially, multiple superior components can reference the same subordinate component, and multiple subordinate components can be referenced by a superior component.

Impact analysis enables you to examine the following types of relationships and dependencies among baseline library components:

Relationship Superior Component Subordinate Component
Source to copybook Like-source component Like-copy component
Composite load to linked load Composite like-load Statically linked like-NCAL or like-load subprogram
Execution JCL to cataloged procedure Execution JCL Cataloged procedure
JCL/Procedure to program name Execution JCL or cataloged procedure Program name in PGM=
JCL/Procedure to data set name Execution JCL or cataloged procedure Data set name in DSN=


The relationship between a subprograms that is dynamically called by a main program is not included in impact analysis.

Consider carefully the subordinate-superior position as well as the type of relationship that exists among the target components when you formulate impact analysis queries. The way that you formulate a query affects the results that are returned.

Questions Answered by Impact Analysis

There are two types of impact analysis data queries. Each query answers a different question about the effect of a proposed change to a component that is managed by ChangeMan ZMF.