ROW Segmentation Region

SELECT mst.SubscriberKey, mst.EmailAddress,mst.Consent_Level_Summary__c,
CASE WHEN Mailing_Country__c = 'US' THEN 'NA'
WHEN Mailing_Country__c = 'MX' THEN 'NA'
WHEN Mailing_Country__c = 'CA' THEN 'NA'
ELSE 'OTHER'
END as SegmentRegion
FROM ep_mr_en_us_w170049_MASTER mst
WHERE SegmentRegion is null