Describes a reminder of a calendar event
| Column | Type | References | Comments |
| id | Integer | Primary key | |
| guid | String | ||
| vdb_id | Integer | ||
| owner_id | Integer | db_person.id | Owner ID |
| calendar_event_id | Integer | db_calendar_event.id | ID of the calendar event object this reminder corresponds to |
| last_reminded_at_utc | Date | Date last reminded at (in case of recurring events) | |
| due_date_utc | Date | Date of the reminder |