SELECT
  SURVEY_YEAR
  , PF_CODE
  , TOTAL_VALUE
FROM
  CONVENIENCE
WHERE
  SURVEY_YEAR = 2018
  AND KIND_CODE = 100
  AND TOTAL_VALUE IS NOT NULL
  
UNION

SELECT
  SURVEY_YEAR
  , PF_CODE
  , TOTAL_VALUE
FROM
  CONVENI_SALE_2018