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firebase.firestore.CollectionReference

db.collection.count

Top / db.collection.count

firebase.firestore.Query

•     /**
       * Returns a query that counts the documents in the result set of this
       * query.
       *
       * The returned query, when executed, counts the documents in the result set
       * of this query without actually downloading the documents.
       *
       * Using the returned query to count the documents is efficient because only
       * the final count, not the documents' data, is downloaded. The returned
       * query can even count the documents if the result set would be
       * prohibitively large to download entirely (e.g. thousands of documents).
       *
       * @return a query that counts the documents in the result set of this
       * query. The count can be retrieved from `snapshot.data().count`, where
       * `snapshot` is the `AggregateQuerySnapshot` resulting from running the
       * returned query.
       */
      count(): AggregateQuery<{count: AggregateField<number>}>;