SELECT case when p.tax1 is null then cast( -1 AS CHAR(60))
else cast( p.tax1 AS CHAR(60)) end
as EXTTAXLINK,p.id as EXTID,
cast( p.productId AS CHAR(60)) as productId,
p.quantity,
p.listprice,
p.discount_percent,
p.discount_amount,
p.comment,
p.tax1,
90 as WLINETYPEID FROM vtiger_inventoryproductrel p join vtiger_invoice i on (p.id = i.invoiceid)