去重就行了
SELECT DISTINCT DBO.S_RECORD.PROBUCT_NUMBER,
DBO.S_BASIC_STATION.RT,
DBO.S_RECORD.ACTUAL_HOURS
FROM DBO.S_RECORD
INNER JOIN DBO.S_BASIC_STATION
ON DBO.S_RECORD.STATION_CODE = DBO.S_BASIC_STATION.STATION_CODE
WHERE DBO.S_RECORD.DATE = '2020-08-19';