About Impact Analysis and Reverse Impact Analysis

Impact analysis identifies the tables, columns, jobs, and transformations that are affected by a change to a selected table or column. Reverse impact analysis identifies the tables, columns, jobs, and transformations that contribute to the content of a selected table or column. Use impact analysis before changing or deleting a metadata object, to see how that change can affect other objects. Use reverse impact analysis to trace the source data that contributes to the content of a selected table or column.

The following figure shows the difference between impact analysis and reverse impact analysis for a selected object.

As shown in the figure, impact analysis traces the impact of the selected object on later objects in the data flow. Reverse impact analysis traces the impact that previous objects in the data flow have had on the selected object.

Analysis is performed on all metadata repositories on the current metadata server. Analysis extends into cubes. You can generate impact and reverse impact analyses for most types of data objects, including columns, tables, external files, information maps, Enterprise Guide projects and associated objects, and the levels and measures in OLAP cubes. You can also generate impact analyses for generated transformations, as described in Performing Impact Analysis on a Generated Transformation.

To perform an analysis, right-click an object in the Inventory tree, Custom tree, or Job Editor and select Analyze. This action opens a new window that contains up to four tabs, which include Impact Analysis, Reverse Impact Analysis, Contents, and Reports. Analytical results appear in the Impact Analysis or Reverse Impact Analysis tabs. In those tabs, you can right-click on the table and select Analyze Columns to determine how that table or job impacts or is impacted by the selected object. Within these tabs, you can also display properties or select Open to view the data in a table. You can also select one of the icons at the top of the tab to view the object in a tree or diagram view or to print the contents.

If you run an analysis and the results do not include objects that you know exist on the system, ask your administrator to verify that you have the appropriate privileges to see these objects. For more information, the administrator should see the SAS Intelligence Platform: Security Administration Guide.