You are given user activity data for Google products. Write a SQL query to calculate the month-over-month growth rate of active users for a specific platform, using Google Maps as the target product. Treat an active user as a distinct user with at least one activity event in that month. Return each month, the active user count, the prior month's active user count, and the month-over-month growth rate as a percentage. For the first month in the result, the prior month and growth rate should be NULL.
| Column | Type | Description |
|---|---|---|
| product_idPK | INT | Unique product identifier |
| product_name | VARCHAR(100) | Google product name |
| platform | VARCHAR(20) | Platform where the product is used |
| Column | Type | Description |
|---|---|---|
| user_idPK | INT | Unique user identifier |
| country_code | VARCHAR(2) | User country code |
| signup_date | DATE | Date the user signed up |
| Column | Type | Description |
|---|---|---|
| event_idPK | INT | Unique event identifier |
| user_id | INT | User who generated the event |
| product_id | INT | Product tied to the event |
| event_date | DATE | Date of the activity event |
| event_type | VARCHAR(30) | Type of user activity |