Managing feature class representations

This topic applies to ArcEditor and ArcInfo only.

Representations allow you to symbolize your data using a flexible, rule-based structure that is stored inside the geodatabase along with your data. Feature classes can support multiple feature class representations simultaneously, so a variety of map products can be derived from a single database without the unnecessary storage of copies of data. The representation of a single feature (called a feature representation) can be modified if necessary, creating a persistent override to the representation rule, which is also stored and maintained within the geodatabase. Representations provide the organizational structure of rule-based symbology while retaining the flexibility to customize the portrayal of individual features.

Representations are a property of feature classes and can be viewed and managed from the Representations tab on the Feature Class Properties dialog box in ArcCatalog.

Dive-in:

When you add a representation to a feature class, two fields (the RuleID field and the Override field) are added to the feature class table to store extra information to tell the feature class how to symbolize its features when a layer is drawn using that representation.

The RuleID field is an integer field that stores a reference to the representation rules, which are stored within system tables of the geodatabase. Since it is an integer field (with a coded value domain), you can manually edit the values in the field to assign a different representation rule to a feature. You can also use the Representation Properties window during an ArcMap editing session or the Calculate Representation Rule geoprocessing tool to do this.

The Override field is a binary large object (BLOB) field that stores feature-specific overrides to the representation rules. Overrides are changes to the representation properties at the feature level and may include changes to feature representation geometry, depending on how the editing behavior of the representation is set.

Using layer files to organize representations

You can use layer files (.lyr) to save a specific way to display data, including the use of a representation present on the source data. Layer files do not store the actual representation rules. They only hold a pointer to which feature class representation to use to render the data. You can create layer files in ArcMap from layers that are symbolized with a feature class representation, or you can create layer files in ArcCatalog that reference a feature class and an associated feature class representation.

Learn about saving layers to a layer file

Using the representation management geoprocessing tools

You can use the tools in the Representation Management geoprocessing toolset in the Cartography toolbox to manage your representations. There are tools to add and remove representations from a feature class, create a layer from a feature class representation, and manage overrides within a feature class representation.

Data types that support representations

Any point, line, or polygon feature class in a personal, file, or ArcSDE geodatabase can support representations. Shapefiles, coverages, annotation feature classes, and dimension feature classes cannot support feature class representations.

Caution:

If you are creating a feature class representation from a symbolized layer in ArcMap, understand that 3D symbols will not be translated to representation rules. A default representation symbol is generated for those features instead.

Layers displayed with the Proportional Symbol, the Quantity by Category, or one of the Chart Symbol renderers cannot be translated to representation rules.

License:

An ArcEditor or ArcInfo license is required to create or edit representations. Any license can be used to view representations.

How to add a representation to a feature class

1. Click Properties on the shortcut menu of the feature class in ArcCatalog or in the Catalog window in ArcMap to open the Feature Class Properties dialog box.
2. On the Representations tab, click New to open the New Representation dialog box.
3. Type a name for the new feature class representation and names for the RuleID and Override fields, or accept the default names. Although you can change the name of a representation later, the names of the RuleID and Override fields cannot be changed. If you plan to have many representations associated with this feature class, it is wise to choose informative representation and field names that are easy to relate to one another.
4. Decide how you want to store changes to geometry:
   • Choose Store change to geometry as representation override to place all modifications to feature representation geometry in the Override field, leaving the Shape field intact.
   • Choose Change the geometry of the supporting feature to force edits made to the feature representation geometry to also alter the geometry of the source feature.

   Learn more about this decision

5. To import representation rules from an existing layer that symbolizes features with a representation, click Select to navigate to the layer on the Select a Feature Layer dialog box. All the representation rules of that layer will be copied into this feature class representation.
6. If the layer specified in the previous step is based on the same feature class as this feature class, you can also choose to assign the representation rules to features by checking the Assign rules to features to match the layer check box. If you are importing representation rules originating from a different feature class, this option will be disabled.
7. Click Next.
8. Modify the representation rule structure, if necessary.
9. Click Finish to create the new representation.

Tip:

If you do not choose the Assign rules to features to match the layer option, the representation rules will be copied into the feature class representation, but all features will have a NULL RuleID. You will need to manually assign representation rules to the features.

Learn how to assign representation rules to features

The New button may be disabled for one of the following reasons:

• You are in an edit session.
• You are unable to obtain a schema lock. Ensure that the layer is not currently being accessed by ArcCatalog or by another ArcMap session.
• You are using ArcView. An ArcEditor or ArcInfo license is required to create representations.

How to create a representation from a symbolized layer in ArcMap

1. In the Table of Contents window in ArcMap, right-click the symbolized layer and click Convert Symbology to Representation on the shortcut menu.
2. In the Convert Symbology to Representation dialog box, type the name of the new feature class representation and the RuleID and the Override fields, or accept the defaults.
3. Decide how you want to store changes to geometry:
   • Choose Store change to geometry as representation override to place all modifications to feature representation geometry in the Override field, leaving the Shape field intact.
   • Choose Change the geometry of the supporting feature to force edits made to the feature representation geometry to also alter the geometry of the source feature.

   Learn more about this decision

4. Decide if you want to convert all the features in the feature class or only those that are visible in the current extent. Also, decide whether or not to add the new feature class representation to the current map. The original layer will still appear in the table of contents regardless of your choice.
5. Click Convert to add a representation to the source feature class, populated with representation rules that correspond to the appearance of the symbols used in the original layer.

Tip:

The Convert Symbology to Representation command may be disabled for one of the following reasons:

• You are in an edit session.
• You are unable to obtain a schema lock. Ensure that the layer is not currently being accessed by ArcCatalog or by another ArcMap session.
• The layer is currently symbolized with a feature class representation.
• The layer's data source is not a point, line, or polygon feature class in a geodatabase. Shapefiles, coverages, annotation feature classes, and dimension feature classes cannot support feature class representations.
• The layer is currently symbolized with the proportional symbol, the quantity by category, or one of the chart symbol categories.
• The layer's data source resides in a geodatabase that has not yet been upgraded to the current release.
• You are using ArcView. An ArcEditor or ArcInfo license is required to create representations.

How to access the properties of a feature class representation

1. Click Properties on the shortcut menu of the feature class in ArcCatalog or in the Catalog window in ArcMap to open the Feature Class Properties dialog box.
2. On the Representations tab, select a feature class representation from the list.
3. Click Properties to open the Representation Properties dialog box to view or modify the names of the RuleID and Override fields, the editing behavior, and the representation rules associated with this representation.

How to remove a representation from a feature class

1. Click Properties on the shortcut menu of the feature class in ArcCatalog or in the Catalog window in ArcMap to open the Feature Class Properties dialog box.
2. On the Representations tab, select a feature class representation from the list.
3. Click Delete to remove the representation, including the RuleID and Override fields and the representation rules associated with this representation, from the feature class.