select distinct(p.hn),concat(pname,fname," ",lname) as pat ,d.vstdate ,v.pdx from dtmain d
left outer join vn_stat v on v.vn=d.vn
left outer join patient p on p.hn=v.hn
left outer join clinicmember c on c.hn=v.hn and c.clinic="001"
where c.clinic="001" and v.vstdate between"2013-01-01" and "2013-01-23"