Welcome to the SQL screen.
The question is on your right: Clean Null Campaign Metrics. Read through the requirements and the one table first.
Run and submit your code as often as you need. You also have five interviewer messages this session - want to talk through your approach, or are you ready to start coding?
You are given a single table of daily StackAdapt campaign performance metrics. Some rows have missing values in impressions, clicks, or spend. Write a SQL query that returns each campaign_name with the number of rows that contain at least one null metric and the average spend after treating null spend values as 0.
This tests whether you can handle incomplete performance data safely in PostgreSQL without dropping rows that still matter for reporting.
| Column | Type | Description |
|---|---|---|
| idPK | INT | Unique row identifier |
| campaign_name | VARCHAR(100) | StackAdapt campaign name |
| metric_date | DATE | Date of the performance record |
| impressions | INT | Number of impressions served |
| clicks | INT | Number of clicks recorded |
| spend | DECIMAL(10,2) | Daily spend in dollars |