Add support for distinct for links

[chouex]

i tried

realm.distinct(Parent.class, "Child");

throw java.lang.UnsupportedOperationException: The field must be indexed before distinct() can be used.
but linked field can not be indexed

and tried

realm.distinct(Parent.class, "Child.id");

throw java.lang.IllegalArgumentException: Field name 'Child.id' does not exist.

compile 'io.realm:realm-android:0.86.0'
android v4.4.4

[emanuelez]

We currently do not support indexing (and consequently distinct) on links. I'll rename your issue and tag it as an enhancement request.

[CatalinPrata]

+1 I agree that this would be a very helpful feature! Thank you! :)

[pradeep2929]

It will work
realmResult.distinct(CONTACT_ID);

[iamcrypticcoder]

+1 This feature will be very helpful and almost mandatory. Is there any alternative solution to this right now ? I really need a solution.

[Zhuinden]

Wait, distinct across links is still not supported, even with Results integration?

[wilburx9]

Any workaround?

[Zhuinden]

Invert your query so that it is not the distinct() that happens across the link.

[SuhasTS]

This would be a very useful feature.
How come sorting works across links and not distinct?

[cmelchior]

Distinct on linked properties should be supported by Core now and there is an internal team needing this functionality, so we should look into lifting this restriction soon.

[RealmBot]

➤ Christan Melchior commented:

Some of the tests capturing the current behavior is here:

https://github.com/realm/realm-java/blob/master/realm/realm-library/src/androidTest/java/io/realm/RealmQueryTests.java#L3103 ( https://github.com/realm/realm-java/blob/master/realm/realm-library/src/androidTest/java/io/realm/RealmQueryTests.java#L3103 )

https://github.com/realm/realm-java/blob/master/realm/realm-library/src/androidTest/java/io/realm/RealmQueryTests.java#L3120 ( https://github.com/realm/realm-java/blob/master/realm/realm-library/src/androidTest/java/io/realm/RealmQueryTests.java#L3120 )

https://github.com/realm/realm-java/blob/master/realm/realm-library/src/androidTest/java/io/realm/RealmQueryTests.java#L3137 ( https://github.com/realm/realm-java/blob/master/realm/realm-library/src/androidTest/java/io/realm/RealmQueryTests.java#L3137 )