Relates defined in ArcMap are essentially the same as simple relationship classes defined in a geodatabase, except that they are saved with the map instead of in a geodatabase.
If a feature class in a geodatabase participates in a relationship class, that relationship class will be immediately available for use. You don't need to relate the tables in ArcMap.
Relates (or relationship classes) are the best way to associate data that has a 1:M relationship.
- Right-click the layer you want to relate, point to Joins & Relates, then click Relate.
You can also click the Table Options button
on an open Table window to access the Relate dialog box. - Choose the field in the layer on which the relate will be based.
- Choose the table or layer to relate to, or load the table from disk.
- Choose the field in the related table on which to base the relate.
- Type a name for the relate.
You'll use this name to access the related data.
- Click OK.
The relate is now established between the two tables. Refer to the topic Accessing related records for information on how to work with relates.