Impact Analysis
Impact analysis is a facility that shows relationships and dependencies among baseline library components. By querying impact analysis data for selected components you can do the following:
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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.
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Avoid product failures that occur when you install a change without considering related components.
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 Impact Analysis wizard takes a bottom-up view of component relationships. You ask a question about a subordinate component, and it tells you about superior components.
In other words, it tells you what components contain a component that you want to change.
Running Impact Analysis
There are three pages in the Impact Analysis wizard. You can go back and forth between the pages using the Next and Back buttons. The Back button is the back arrow button at the upper left corner of the window.
To start the Impact Analysis wizard, right click on a ChangeMan instance and choose Impact Analysis. You can also right click on an application, a library type, or a component, and the wizard form will be automatically filled in based on the item you selected.
Search Arguments Page
The wizard will then launch, and the Search Arguments page will display.
Update the fields in the Search Arguments page and press Next to begin the search.
Fields on the Search Arguments Page
The following table describes the fields on the Search Arguments page.
| Field | Required | Description |
|---|---|---|
| Search arguments | Specify the subordinate component or components you want to investigate. | |
| Bottom component | Required | Enter the name of a subordinate component. Valid values Include: Like-copy component name Statically linked like-NCAL or like-load subprogram name Cataloged procedure name Program name or string in JCL PGM= statement Data set name or string in JCL DSN= statement Valid formats include: Full component name or string Component name pattern or string ending in \ The first character in this field cannot be . |
| Mixed case | Optional | Select to use the exact text entered in the bottom component name to search for relationships. If not selected, it will fold the text entered for subordinate component name into upper case before searching for relationships. |
| Bottom library type | Optional | You can, optionally, select the library type of the subordinate component. If no library type is selected, all library types will be searched. To clear the selection, select "(None)", which is the first entry at the top of the drop down list. Do not select any library type if the subordinate component is one of the following, which are stored in impact analysis as character strings rather than as components with library types: Cataloged procedure name Program name or string in JCL PGM= statement Data set name or string in JCL DSN= statement |
| Bottom application | Optional | You can, optionally, select the application of the subordinate component. If no application is selected, all applications types will be searched. To clear the selection, select "(None)", which is the first entry at the top of the drop down list. |
| Field | Required | Description |
|---|---|---|
| Relationship | Required | Select the relationship between the superior and subordinate components that you want to evaluate. The possible relationships are as follows: |
| Copybook (Source to copybook) Subroutine (Composite load to linked load) JCL Proc (Execution JCL to cataloged procedure) JCL Pgm (JCL/Procedure to program name) JCL DSN (JCL/Procedure to data set name) | ||
| Result filters | Specify filter criteria if you want to see a subset of the superior components that have a relationship to the component you are investigating. | |
| Top component | Optional | You can, optionally, enter the name of a superior component. Valid formats Include: Full component name Component name pattern Asterisk () for all names Blank, which defaults to \ |
| Mixed case | Optional | Select to use the exact text entered in the top component name to filter results. If not selected, it will fold the text entered for top component name into upper case before searching for relationships. |
| Top library type | Optional | You can, optionally, select the library type of the superior component. If no library type is selected, the results will not be filtered by library type. To clear the selection, select "(None)", which is the first entry at the top of the drop down list. |
| Top application | Optional | You can, optionally, select the application of the superior component. If no application is selected, the results will not be filtered by application. To clear the selection, select "(None)", which is the first entry at the top of the drop down list. |
Top Components Page
The Top Components page displays at the end of the search.
The top half of the Top Components page echoes the search criteria and results filter criteria for the subordinate component that you specified on the preceding Search Arguments page.
The bottom half of the page shows a list of superior components that satisfy the search and filter criteria that you specified.
If you want to go back and start a new search, press Back button, which is a back arrow at the upper left corner of the window.
To display the subordinate components for any of the components listed, select a component on the list and press Next.
Fields on the Top Components Page
This table describes the fields on the Top Components page.
| Field | Description |
|---|---|
| List of components which reference | |
| Application | Application that you specified in the Search Arguments. |
| Type | Library type that you specified in the Search Arguments. |
| Name | Bottom (subordinate) component name that you specified in the Search Arguments. |
| Relationship | Relationship that you specified in the Search Arguments. |
| And match these criteria | |
| Application | Application that you specified in the Results Filter. |
| Type | Library type that you specified in the Results Filter. |
| Name | Top (superior) component name that you specified in the Results Filter. |
| Results list | |
| Component | Displays the name of superior components that satisfy the selection and filter criteria that you specified on the Search Arguments page. |
| Found in Appl:Libtype | Displays the application and library type of the library where the superior component is baselined. |
Bottom Components Page
The Bottom Components page displays the subordinate components.
The Bottom Components page lists subordinate components contained in the selected superior component that have the same relationship type as your original query.
If you want to go back and query for additional information, press Back button, which is a back arrow at the upper left corner of the window.
To end the wizard, press the Close button.