//----------------------------------------------------------------------------------------
function get_sql_for_customer_inquiry($from, $to, $cust_id = ALL_TEXT, $filter = ALL_TEXT, $show_voided = 0)
{
    $date_after = date2sql($from);
    $date_to = date2sql($to);
      $sql = "SELECT 
          trans.type, 
        trans.trans_no, 
        trans.order_, 
        trans.reference,
        trans.tran_date, 
        trans.due_date, 
        debtor.name, 
        branch.br_name,
        debtor.curr_code,
        IF(prep_amount, prep_amount, trans.ov_amount + trans.ov_gst + trans.ov_freight 
            + trans.ov_freight_tax + trans.ov_discount)    AS TotalAmount,"
        . "IF(trans.type IN(".implode(',',  array(ST_CUSTCREDIT,ST_CUSTPAYMENT,ST_BANKDEPOSIT))."), -1, 1)
                *(IF(prep_amount, prep_amount, trans.ov_amount + trans.ov_gst + trans.ov_freight 
            + trans.ov_freight_tax + trans.ov_discount)-trans.alloc) Balance, 
        debtor.debtor_no,";
        $sql .= "trans.alloc AS Allocated,
        ((trans.type = ".ST_SALESINVOICE." || trans.type = ".ST_JOURNAL.")
            AND trans.due_date < '" . date2sql(Today()) . "') AS OverDue ,
        Sum(line.quantity-line.qty_done) AS Outstanding,
        Sum(line.qty_done) AS HasChild,
        prep_amount
        FROM "
            .TB_PREF."debtor_trans as trans
            LEFT JOIN ".TB_PREF."debtor_trans_details as line
                ON trans.trans_no=line.debtor_trans_no AND trans.type=line.debtor_trans_type
            LEFT JOIN ".TB_PREF."voided as v
                ON trans.trans_no=v.id AND trans.type=v.type
                        LEFT JOIN ".TB_PREF."audit_trail as audit ON (trans.type=audit.type AND trans.trans_no=audit.trans_no)
                        LEFT JOIN ".TB_PREF."users as user ON (audit.user=user.id)
            LEFT JOIN ".TB_PREF."cust_branch as branch ON trans.branch_code=branch.branch_code
            LEFT JOIN ".TB_PREF."debtors_master as debtor ON debtor.debtor_no = trans.debtor_no" // exclude voided transactions and self-balancing (journal) transactions:
            ." WHERE";
    if ($filter == '2')
        $sql .= " ABS(IF(prep_amount, prep_amount, trans.ov_amount + trans.ov_gst + trans.ov_freight + trans.ov_freight_tax + trans.ov_discount)-trans.alloc)>"
            .FLOAT_COMP_DELTA;
    else {
        $sql .= " trans.tran_date >= '$date_after'
            AND trans.tran_date <= '$date_to'";
    }
    if (!$show_voided)     
             $sql .= " AND ISNULL(v.date_) AND (trans.ov_amount + trans.ov_gst + trans.ov_freight + trans.ov_freight_tax + trans.ov_discount) != 0";
       if ($cust_id != ALL_TEXT)
           $sql .= " AND trans.debtor_no = ".db_escape($cust_id);
       if ($filter != ALL_TEXT)
       {
           if ($filter == '1')
           {
               $sql .= " AND (trans.type = ".ST_SALESINVOICE.") ";
           }
           elseif ($filter == '2')
           {
               $sql .= " AND (trans.type <> ".ST_CUSTDELIVERY.") ";
           }
           elseif ($filter == '3')
           {
            $sql .= " AND (trans.type = " . ST_CUSTPAYMENT 
                    ." OR trans.type = ".ST_BANKDEPOSIT." OR trans.type = ".ST_BANKPAYMENT.") ";
           }
           elseif ($filter == '4')
           {
            $sql .= " AND trans.type = ".ST_CUSTCREDIT." ";
           }
           elseif ($filter == '5')
           {
            $sql .= " AND trans.type = ".ST_CUSTDELIVERY." ";
           }
        if ($filter == '2')
        {
            $today =  date2sql(Today());
            $sql .= " AND trans.due_date < '$today'
                AND (trans.ov_amount + trans.ov_gst + trans.ov_freight_tax + 
                trans.ov_freight + trans.ov_discount - trans.alloc > 0) ";
        }
       }
    $sql .= " GROUP BY trans.trans_no, trans.type";
       return $sql;
}