LEFT JOIN cust_bill ON ( eventtable = 'cust_bill' AND tablenum = invnum )
LEFT JOIN cust_pkg ON ( eventtable = 'cust_pkg' AND tablenum = pkgnum )
LEFT JOIN cust_pay ON ( eventtable = 'cust_pay' AND tablenum = paynum )
LEFT JOIN cust_bill ON ( eventtable = 'cust_bill' AND tablenum = invnum )
LEFT JOIN cust_pkg ON ( eventtable = 'cust_pkg' AND tablenum = pkgnum )
LEFT JOIN cust_pay ON ( eventtable = 'cust_pay' AND tablenum = paynum )