select AVG(TOTAL_VALUE) as SA_MEDIAN
from (
    select TOTAL_VALUE
    from CONVENIENCE
    where SURVEY_YEAR=2019 and KIND_CODE='100'
    order by TOTAL_VALUE
    limit 2 - (select count(*)%2 from CONVENIENCE where SURVEY_YEAR=2019 and KIND_CODE='100')
    offset (select (count(*)-1) /2 from CONVENIENCE where SURVEY_YEAR=2019 and KIND_CODE='100')
);