Geoprocessing considerations for subtypes

Subtypes are a way of categorizing 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 could be coded to represent three subtypes:

Code	Description
0	Deciduous
1	Coniferous
2	Mixed

Example subtype code and corresponding description

Tools for managing subtypes

Add SubtypeRemove SubtypeSet Default SubtypeSet Subtype Field

When is it important to know if 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 shapefile, and some geoprocessing tools do not support subtype outputs.

Determining if you have subtypes

1. In the Catalog tree, right-click the feature class or table.
2. Click Properties.
3. Click the Subtypes tab.

If the feature class has subtypes, the subtype field is listed in the subtype field category.

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, .dbfs, and in_memory) will succeed, but the output will obviously 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:

ProjectFeature Class To Feature ClassTable To TableCopyCopy FeaturesCopy RowsAppend