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.

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public class Activity extends Record {
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    @Indexed private Date activityDate;
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    @Indexed private User activityUser;
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    @Indexed private String groupLead;
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     /* Getters and setters */
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 }
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public class User extends Record {
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    @Indexed private String name;
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    /* Getters and setters */
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}

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.

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/* Get the user */
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User user = Query.from(User.class).where("name = 'John Smith'").first();
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/* Get the user's list of activities */
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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.

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List<Activity> activities = Query.from(Activity.class)
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            .where("activityUser/name = 'John Smith'")
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            .selectAll();