Retreat Reminder Query

SELECT c.id AS contact_id, v.name, c.display_name FROM
(SELECT id FROM civicrm_event WHERE event_type_id=10 AND is_template=0 LIMIT 1) e
JOIN civicrm_option_value v ON v.option_group_id=2 AND v.name LIKE '%Registration Completed'
JOIN civicrm_tag t ON t.name='No Selected Retreat'
JOIN civicrm_activity a ON a.activity_type_id=v.VALUE
JOIN civicrm_activity_contact ac ON ac.activity_id=a.id AND ac.record_type_id=3
JOIN civicrm_entity_tag et ON et.entity_id=ac.contact_id AND et.entity_table='civicrm_contact' AND et.tag_id=t.id
JOIN civicrm_contact c ON c.id=ac.contact_id
WHERE c.is_deleted=0 GROUP BY c.id