Conventions used

There are a number of text conventions used throughout this book.

Code in text: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: “It specifies the structure of the data with fields such as device_id, country, event_type, and event_ts.”

A block of code is set as follows:

val updateSilver: DataFrame = bronzeData
     .select(from_json(col("value"), jsonSchema).alias("value"))
     .select(
       col("value.device_id"),
       col("value.country"),
       col("value.event_type"),
       col("value.event_ts")
     )
     .dropDuplicates("device_id", "country", "event_ts")

Any command-line input or output is written as follows:

argo submit my-first-workflow.yaml --serviceaccount=spark -n spark-app --watch

Bold: Indicates a new term, an important word, or words that you see onscreen. For instance, words in menus or dialog boxes appear in bold. Here is an example: “You can find your policy in Shared access policies in the left-side of the Azure Event Hubs service.”

Tips or important notes

Appear like this.