如何为查询创建索引使用文档ID Cloud Firestore

Question

I am using this query in my android app :

        fireStoreQuestions.document(subject).collection(subject)
            .whereEqualTo("reviewed", true)
            .whereGreaterThan(FieldPath.documentId(), randomId)
            .limit(1)
            .get()

I want to know how to add an index to this query in cloud firestore. I don't know how to represent the document id in the index.

Answer 1

You can create the index manually in your Firebase Console or if you are using Android Studio, you'll find in your logcat a message that sounds like this:

W/Firestore: (0.6.6-dev) [Firestore]: Listen for Query(subject where reviewed == true and id > randomId) failed: Status{code=FAILED_PRECONDITION, description=The query requires an index. You can create it here: https://console.firebase.google.com/project/ ...

So you can simply click on that link or copy and paste the url into a web broswer and you index will be created automatically.