Handling Missing Values | Dataford Interview Questions

Describe how you would approach a new data set with missing values at YipitData.

Use the source_observations table and write a query that profiles missing values in metric_value. The result should summarize the completeness of the column so the data can be assessed before analysis.

Output

Return one row with total_records, missing_metric_value, non_missing_metric_value, and missing_percentage.
Calculate missing_percentage as the percentage of all records with a missing metric_value, rounded to two decimal places.

Schema

source_observations

Column	Type	Description
observation_idPK	INT	Unique identifier for the observation
source_system	VARCHAR(50)	System that supplied the observation
status	VARCHAR(20)	Processing status of the observation
metric_value	DECIMAL(10,2)	Numeric value being checked for completeness

Your question is Handling Missing Values. Start with the requirements and the one table in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem

Describe how you would approach a new data set with missing values at YipitData.

Output

Return one row with total_records, missing_metric_value, non_missing_metric_value, and missing_percentage.
Calculate missing_percentage as the percentage of all records with a missing metric_value, rounded to two decimal places.

Schema

source_observations

Column	Type	Description
observation_idPK	INT	Unique identifier for the observation
source_system	VARCHAR(50)	System that supplied the observation
status	VARCHAR(20)	Processing status of the observation
metric_value	DECIMAL(10,2)	Numeric value being checked for completeness

Your question is Handling Missing Values. Start with the requirements and the one table in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.