This is what i am doing at the min:
LOAD ProteanTPObjectID,
PurchaseInvNo,
CalendarLink,
ProteanInvCreateDate,
ProteanInvValue,
ProteanInvStatus,
ProteanInvSite,
ProteanInvType,
DocuWareInvTotalAmount,
DocuWareInvStatus,
ProteanTPDesc,
ProteanInvDesc
FROM $(datasource)PI_DocUWare_Invoice.qvd (qvd);
WHERE ( ProteanInvSite <> 'S05'
AND ProteanInvSite <> 'S06'
AND ProteanInvSite <> 'S35')
AND (LEFT(PurchaseInvNo,3) <> 'POI');