When you add a feature class with subtypes to a map or scene, a feature layer is created and symbolized with unique values symbology, in which each subtype is assigned a unique symbol class. Alternatively, you can add the feature class to the map or scene as a preset subtype group layer. Subtype group layers are composite feature layers that contain multiple sublayers called subtype layers. Each subtype layer corresponds to one subtype in the source feature class or feature service. This way, each sublayer can be symbolized independently.
Subtype group layers draw more efficiently than an equivalent set of individual layers because a single call is made to the source data for the entire subtype group layer when panning, zooming, or otherwise redrawing. You set the layer properties, including symbology, scale ranges, and label settings, for each subtype layer in the composite subtype group layer individually.
Both subtype group layers and subtype layers can be used as input to geoprocessing tools. When a subtype group layer is used as a geoprocessing input, all features from the source are considered (unless there is a definition query set on the subtype group layer).
Add a subtype group layer to a map or scene
To add a subtype group layer to a map or scene, complete the following steps:
- On the Map tab, in the Layer group, click the Add Data drop-down menu , and click Subtype Group Layer .
- On the Choose one or more items with subtypes dialog box, browse to the dataset and click OK to add it to the map or scene.
There are a few limitations to subtype group layers. Subtype group layers cannot be joined to another layer or table, and you cannot create a relationship between a subtype group layer and another layer or table. Relationship classes that are defined in the geodatabase are exempt, however.
You cannot open the attribute table for the subtype group layer. You can only open the attribute tables for the subtype layers within it. You cannot perform a selection on the subtype group layer; you must select features from the subtype layers.
Subtype layers cannot be dragged out of their parent subtype group layer. While you can set most layer properties on subtype layers independently, there are some that are inherited from the parent subtype group layer and cannot be changed from the subtype layer. The following properties cannot be set or specified from the subtype layer: