Before running SQL queries on your dataset, you must register a temporary view for the dataset.

The following operation registers a characters table and then queries it to find all characters that are 100 or older:

val characters = spark.read.format("mongodb").as[Character]
characters.createOrReplaceTempView("characters")
val centenarians = spark.sql("SELECT name, age FROM characters WHERE age >= 100")
centenarians.show()