The Schemas filter group in the Filter Pane of the Impact Analysis - DB tab consists of a checkbox list with search filter:

A schema is collection of database objects, including logical structures such as tables, views, sequences, stored procedures, synonyms, indexes, clusters, and database links.

With this filter, you can limit the displayed BI data to the nodes which are available in the selected database schema(s).

Start typing a schema name you are looking for in the search control, and the list will be limited to schemas that contain your input.

Tip
To determine a schema for the selected object, you can use View Impacted Objects.

 

There is an additional item (All) in the list of schemas. Use it to toggle between all schemas being selected and all schemas being unselected.

If all schemas are selected, or none of them, then the Schemas filter is not applied, and it does not limit the data displayed.

 

 
See also

Global