select distinct substring(name,1,1) from stamps ,color_master where color_master.color_code=stamps.color_code and color_master.color='Blue' and year(stamps.issue_date)=1973 and stamps.serial_no='0685' order by substring(name,1,1)
IndianPost
Color >> Blue >> Issue Date >> year >> 1973 >> Serial Number >> 0685 >> Alpha >> T >>