Object references
Dari supports querying relationships using the field/subfield path notation in where methods. The following models demonstrate the use case of finding all activities for a particular user. In these models, the Activity.activityUser field is of type User.
public class Activity extends Record {
@Indexed private Date activityDate;
@Indexed private User activityUser;
@Indexed private String groupLead;
/* Getters and setters */
}
public class User extends Record {
@Indexed private String name;
/* Getters and setters */
}There are two ways to find activities by a specific user. You can first query for the user, and then query for activities by that user.
/* Get the user */
User user = Query.from(User.class).where("name = 'John Smith'").first();
/* Get the user's list of activities */
List<Activity> activities = Query.from(Activity.class).where("activityUser = ?", user).selectAll();A second, more efficient way, is to use a single query that incorporates path notation.
List<Activity> activities = Query.from(Activity.class)
.where("activityUser/name = 'John Smith'")
.selectAll();
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