ลองดูนะครับ
select pt.hn,concat(pt.pname,pt.fname," ",pt.lname)as ptname,n.name as nation_name
from patient pt
left outer join nationality n on n.nationality=pt.nationality
where pt.hn=xxxxxxx
หรือสร้าง variable มา 1 ตัว
value := GetSQLStringData(' select n.name as nationallity_name from patient pt '+
' left outer join nationality n on n.nationality=pt.nationality '+
' where pt.hn=DBPipeline['hn'] ');