Write a query to identify top-performing user cohorts based on session frequency.
Treat each signup month as a cohort and measure performance by average sessions per registered user. Include cohorts with no sessions, rank cohorts by this average, and return the top three ranks.
cohort_month, users_in_cohort, total_sessions, avg_sessions_per_user, and cohort_rank.| Column | Type | Description |
|---|---|---|
| user_idPK | INT | Unique user identifier |
| signup_date | DATE | Date the user signed up |
| Column | Type | Description |
|---|---|---|
| session_idPK | INT | Unique session identifier |
| user_id | INT | User associated with the session |
| session_start | TIMESTAMP | Session start timestamp |
| client_platform | VARCHAR(30) | Platform used for the session |