A direct association is an association between any two classes of objects where the association values are stored on one of the objects directly.
A direct association can be in the forward direction, that is from group to account, and in the reverse direction, that is, from account to group. Creating a direct association in the forward direction lets you manage the accounts that belong to a group from the group side of the association. Creating a direct association in the reverse direction, that is a reverse association, lets you manage the association from the account side of the relationship.
Direct associations in the forward direction coincide with the natural representation of the associative information about the endpoint objects, that is, where the group stores account members. Direct associations in the reverse direction are the reverse of this representation, as they define groups to which an account belongs, even if the native system does not store such information.
Typically, it is common to establish both directions of an association at the same time, that is, both the direct and reverse associations. You can use the Direct Association dialog to create and edit both associations at the same time.
In a direct association, a group directly stores the directory-relative DNs of the accounts which belong to it. Therefore you create a direct association between classes when you map groupOfNames.member to inetOrgPerson.cn.
Note: Both of these objectclasses are part of the inetOrgPerson schema. They differ only in minor implementation details on the endpoint, that is, groupOfUniqueNames stores its members as a set rather than a list helping ensure that the associated entries are unique.
In direct associations, references are persisted directly into a multivalued attribute on the endpoint. For example, in LDAP, a group's member attribute directly stores reference to the accounts it contains.
When creating associations between classes for JDBC connectors, we recommend that you use direct associations for one to one, and one to many relationships. For many to many relationships (for example, the relationship between Account’s memberOf and Group’s members), use an a indirect association instead of a direct association.
Example: Direct Association
The following example shows a direct association that has been mapped between an account class and a finance class. The finance class stores the accounts that belong to it in its member attribute.
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