When dealing with complex schemas with various defined types, it can be very helpful for the mapping process, to just focus on the schema information that is relevant for the alignment. On the other hand, by default a type that is relevant for you might not have been classified as mapping relevant - in this case you would like to change the classification.
Which types in a schema are classified as mapping relevant has various effects. For one, only the mapping relevant types are displayed in the Schema Explorer or can be used for creating a relation. Also, when loading source data, usually only instances of mapping relevant types are loaded.
You can customize the mapping relevant types for the source and target schema separately, the only precondition is that you have loaded the respective schema.
The commands for configuring the mapping relevant types are available in the Edit menu and in the application tool bar. Choose Edit mapping relevant source types or Edit mapping relevant target types depending on which configuration you want to change.
A dialog will open that shows the complex types defined in the schema, grouped by namespace. Types that are already used in the alignment will not be shown, as these are mapping relevant per definition. For each type a checkbox is provided, that allows you to enable or disable its status as mapping relevant.
Classifying a type as not mapping relevant can also be done through the context menu of a selected type, e.g. in the Schema Explorer. In the context menu select the Exclude type from mapping command.