Architecting and designing > Data modeling > Components of an entity relation diagram > Objects in an ERD > Access paths
  
Access paths
An Access Path determines how an individual record in the entity is found. The value of the attribute or attributes that make up the access path might be unique. If they are, the access path represents either the primary key or a candidate key.
Access paths correspond to indexes in the physical data model.
Only one primary key is permitted for any entity. However, there can be more than one unique access path.
This graphic is described in the surrounding text.
To add, rename or delete an access path, click the Access Path tab in the Entity editor.
Note If an entity definition is deleted from the model, all associated access path definitions are also deleted.
If an attribute is removed from the entity definition, it is automatically removed from all access paths of that entity.
To add an access path
1 Click the Access Path tab in the entity editor, and then click New.
2 Type a name for the access path.
3 Select Unique if the access path represents a candidate key for the entity.
4 Select Clustered if records with the same values should be clustered in the database.
5 Select the attributes to be included in the Access Path from the list of Attributes in Entity, and then click the right arrow.
To edit an access path
1 Click the Access Path tab in the entity. Select the specific access path from list.
2 To add additional attributes to the access path, select the attributes from the list of Attributes in Entity, and then click the right arrow.
3 To remove attributes from the access path, select the attributes from the list of Attributes in Index, and then click the left arrow.
4 To rename an access path, overtype the name in the list box.
See also
The PK access path
Objects in an ERD