nerdexam
GoogleGoogle

PROFESSIONAL-DATA-ENGINEER · Question #136

PROFESSIONAL-DATA-ENGINEER Question #136: Real Exam Question with Answer & Explanation

Sign in or unlock PROFESSIONAL-DATA-ENGINEER to reveal the answer and full explanation for question #136. The question stem and answer options stay visible for context.

Submitted by fernanda_arg· Mar 30, 2026Building and operationalizing data processing systems

Question

You are using Google BigQuery as your data warehouse. Your users report that the following simple query is running very slowly, no matter when they run the query: SELECT country, state, city FROM [myproject:mydataset.mytable] GROUP BY country You check the query plan for the query and see the following output in the Read section of Stage:1: What is the most likely cause of the delay for this query?

Options

  • AUsers are running too many concurrent queries in the system
  • BThe [myproject:mydataset.mytable] table has too many partitions
  • CEither the state or the city columns in the [myproject:mydataset.mytable] table have too many NULL values
  • DMost rows in the [myproject:mydataset.mytable] table have the same value in the country column, causing data skew

Unlock PROFESSIONAL-DATA-ENGINEER to see the answer

You've previewed enough free PROFESSIONAL-DATA-ENGINEER questions. Unlock PROFESSIONAL-DATA-ENGINEER for full answers, explanations, the timed quiz mode, progress tracking, and the master PDF. Question stem and options stay visible so you can still see what's on the exam.

Topics

#BigQuery performance#Data skew#Query optimization#Distributed computing
Full PROFESSIONAL-DATA-ENGINEER PracticeBrowse All PROFESSIONAL-DATA-ENGINEER Questions