Appending related fields with a join

This topic applies to ArcEditor and ArcInfo only.


Although relationship classes can be both created and edited in ArcInfo and ArcEditor, they are read-only in ArcView. The feature classes participating in a relationship class will also be read-only in ArcView.

The fields of a related class are not automatically joined to a class's attribute table. This is because one-to-many and many-to-many cardinalities do not support this type of visualization. Also, a given table or feature class may participate in multiple relationship classes that access a large number of related fields, most of which you might not need for a given task.

For one-to-one and many-to-one (really the same as a one-to-one) relationship classes, use an ArcMap join to append the related fields from a specific related class to a table. This helps avoid cluttering it with fields you do not need. You can create a join based on an existing relationship class, which is quicker than specifying all the properties normally needed to define a join. Once you have created the join, the fields from the related feature class or table are added to your feature layer. You can use these fields for labeling, symbolizing, and querying your features.

The Attribute dialog box always provides access to all of a class's related fields, whether or not a join has been created.

  1. Right-click the feature layer in the ArcMap table of contents.
  2. Point to Joins and Relates and click Join.
  3. Click the Join Options drop-down arrow and click Join data based on a predefined relationship class.
  4. Click the drop-down arrow to get a list of relationship classes, then click the relationship class.
  5. Click OK.
  6. You can now use the related fields for labeling, symbolizing, and querying your features.

If the relationship class is one-to-many, each feature can have multiple related objects. In this case, the attributes of the first related object are joined to the feature.
ArcMap has tools for editing relationships. Learn more about editing relationships.

Published 6/7/2010