Rimozione dei record duplicati

Puoi provare la prossima query:

select  SS.sightseeingId, SS.SightseeingName, SS.displayPrice,  MAX(SST.fromDate)
from      tblSightseeings SS inner join 
              tblSightseeingTours SST on SS.sightseeingId =  SST.sightseeingId
where    SS.isActive = 1 and SS.isDisplayOnMainPage = 1
GROUP by SS.sightseeingId, SS.SightseeingName, SS.displayPrice