You can categorize data by creating subsets of features in a feature class or objects in a table that share the same attributes. Subtypes are implemented by creating coded values of the data type short or long integer. Each integer value represents a feature in the subtype. For example, the cover types in a feature class about forest land use can be coded to represent the following three subtypes:
| Code | Description |
|---|---|
0 | Deciduous |
1 | Coniferous |
2 | Mixed |
Tools for managing subtypes
The following tools are used to manage subtypes:
When it's important to know whether subtypes are present
Subtypes in a feature class or table are in many cases still relevant after the feature class or table has been processed. Subtypes are not kept when converting to shapefiles, and some geoprocessing tools do not support subtype outputs.
Determine whether subtypes exist
To determine whether subtypes exist, complete the following steps:
- In the Catalog pane, right-click the feature class or table.
- Click Data Design > Subtypes.
If the feature class or table has subtypes, the subtype is included in the Subtypes view.
Rules
Subtypes are only supported in geodatabase tables and feature classes. If the tools below are used on data with subtypes, the output that is generated will also contain the subtypes. A conversion to any format other than geodatabase (for example, shapefiles, dBASE files, and memory) will succeed, but the output will not have subtypes. The output will still contain the original subtype field and the code value, but it will not be designated as a subtype, and the subtype description will be lost.
The following tools support subtypes when processing features between geodatabases: