SELECT o.hn,o.vstdate,o.nextdate,o.nexttime,d.name AS doctor_name,p.pname,p.fname,p.lname ,c.name AS clinic_name,
p.moopart,p.tmbpart,p.amppart
FROM oapp o
LEFT OUTER JOIN patient p ON p.hn = o.hn
LEFT OUTER JOIN clinic c ON c.clinic = o.clinic
LEFT OUTER JOIN doctor d ON d.code = o.doctor
WHERE o.nextdate BETWEEN '2006-09-01' AND '2006-09-30' AND o.clinic IN (SELECT clinic FROM clinic WHERE chronic = "Y")