Error getting Apprenticeship Standard details- : Column 'ao_code' in field list is ambiguous SELECT standards.standard_id, standards.status, standard_name, lev, funding, ref, type, epa.epa, ao_code, lars_id, standards.industry_id, industry, lars_url, ifate_url, award_org, practical_period, gateway_period, ao_thumb
  FROM standards 
  LEFT JOIN award_org ON standards.ao_code=award_org.award_org_id 
  LEFT JOIN industries ON standards.industry_id=industries.industry_id
  LEFT JOIN epa ON standards.standard_id=epa.standard_id
  WHERE standard_id=19 
  AND epa.latest_ver=1
  AND standards.status='L' 
  AND `type`='S';