Write a SQL query to find the second-highest premium policy within each reinsurance category at Munich Reinsurance America. Return only categories with at least two distinct non-null premium values. If multiple policies share the second-highest premium, return all tied policies.
reinsurance_category, policy_id, policy_number, and premiumreinsurance_category, then policy_id| Column | Type | Description |
|---|---|---|
| category_idPK | INT | Unique reinsurance category identifier |
| category_name | VARCHAR(100) | Name of the reinsurance category |
| Column | Type | Description |
|---|---|---|
| policy_idPK | INT | Unique policy identifier |
| policy_number | VARCHAR(30) | Business policy number |
| category_id | INT | Related reinsurance category |
| premium | NUMERIC(14,2) | Policy premium amount |