Your question is Clean Null Campaign Metrics. Start with the requirements and the one table on the right.
Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.
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 |