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Exercise

Analyzing incomplete records

In an effort to reduce the number of missing vehicle_body_type values going forward, your team has decided to embark on a campaign to educate issuing agencies on the need for complete data. However, each campaign will be customized for individual agencies.

In this exercise, your goal is to use the current missing data values to prioritize these campaigns. You will write a query which outputs the issuing agencies along with the number of records attributable to that agency with a NULL vehicle_body_type. These records will be listed in descending order to determine the order in which education campaigns should be developed.

Instructions

100 XP
  • Specify two columns for the query results: issuing_agency and num_missing (the number of missing vehicle body types for the issuing agency).
  • Restrict the results such that only NULL values for vehicle_body_type are counted.
  • Group the results by issuing_agency.
  • Order the results by num_missing in descending order.