Google Cloud Professional Data Engineer — Question 48

You work for a large fast food restaurant chain with over 400,000 employees. You store employee information in Google BigQuery in a Users table consisting of a FirstName field and a LastName field. A member of IT is building an application and asks you to modify the schema and data in BigQuery so the application can query a FullName field consisting of the value of the FirstName field concatenated with a space, followed by the value of the LastName field for each employee. How can you make that data available while minimizing cost?

Answer options

• A. Create a view in BigQuery that concatenates the FirstName and LastName field values to produce the FullName.
• B. Add a new column called FullName to the Users table. Run an UPDATE statement that updates the FullName column for each user with the concatenation of the FirstName and LastName values.
• C. Create a Google Cloud Dataflow job that queries BigQuery for the entire Users table, concatenates the FirstName value and LastName value for each user, and loads the proper values for FirstName, LastName, and FullName into a new table in BigQuery.
• D. Use BigQuery to export the data for the table to a CSV file. Create a Google Cloud Dataproc job to process the CSV file and output a new CSV file containing the proper values for FirstName, LastName and FullName. Run a BigQuery load job to load the new CSV file into BigQuery.

Correct answer: A

Explanation

Creating a view in BigQuery is the most cost-effective solution because it does not require additional storage or data manipulation, allowing real-time querying of the FullName without altering the existing structure. The other options involve more complex processes that incur higher costs, such as updating the table, creating new tables, or exporting and importing data.