How to parse nested JSON objects in spark sql ?

Lets consider reading a json file and print the schema. And this follows as:

DataFrame df = sqlContext.read().json("/path/to/file").toDF();
    df.registerTempTable("df");
    df.printSchema();

Here nested objects is selected inside a struct type as:

DataFrame app = df.select("app");
        app.registerTempTable("app");
        app.printSchema();
        app.show();
DataFrame appName = app.select("element.appName");
        appName.registerTempTable("appName");
        appName.printSchema();
        appName.show();

Here alternatively try by using below query:

val nameAndAddress = sqlContext.sql("""
    SELECT name, address.city, address.state
    FROM people
""")
nameAndAddress.collect.foreach(println)

Another method is by doing it straight from the SQL query as follows:

Select apps.element.Ratings from yourTableName

Here array will be returned and the elements can be accessed easily inside. Alternatively, online Json viewer is used when working with large JSON structures.