- $min_sdate = $cust_bill_pkg->sdate if $cust_bill_pkg->sdate < $min_sdate;
- $max_edate = $cust_bill_pkg->edate if $cust_bill_pkg->edate > $max_edate;
+ $min_sdate = $cust_bill_pkg->sdate
+ if length($cust_bill_pkg->sdate) && $cust_bill_pkg->sdate < $min_sdate;
+ $max_edate = $cust_bill_pkg->edate
+ if length($cust_bill_pkg->edate) && $cust_bill_pkg->edate > $max_edate;