I want to calculate the bond balance using amount saved in the database and bond amount inputted on a form then insert the result to the database plus the other information. am using php and mysql. below is the code I have
if (isset($_POST['submit'])) {
$ref_no = mysqli_real_escape_string($dbc, $_POST['ref_no']);
$cargo_des = mysqli_real_escape_string($dbc, $_POST['cargo_des']);
$te_no = mysqli_real_escape_string($dbc, $_POST['te_no']);
$bond = mysqli_real_escape_string($dbc, $_POST['bond']);
$bond_no = mysqli_real_escape_string($dbc, $_POST['bond_no']);
$bond_amount = mysqli_real_escape_string($dbc, $_POST['bond_amount']);
$date_lodged = mysqli_real_escape_string($dbc, $_POST['date_lodged']);
//$bond_balance = mysqli_real_escape_string($dbc, $_POST['bond_balance']);
$query = mysqli_query ($dbc, "SELECT amount FROM bond");
while( $row = mysqli_fetch_array($query) ) {
echo $row['amount'];
}
$bond_balance = 0;
$examout = $row['amount'];
$amount = $_POST['bond_amount'];
$bond_balance = $examout - $amount;
$q = "INSERT INTO new_bond (ref_no, cargo_des, te_no, bond, bond_no, bond_amount, date_lodged) "
. "VALUES ('$ref_no','$cargo_des','$te_no','$bond','$bond_no','$bond_amount','$date_lodged','$bond_balance')";
$r = mysqli_query($dbc, $q) or die(mysqli_error($dbc));
if ($r) {
echo '<script>alert("Success")</script>';
echo "<script>window.open('?page=new_bond','_self')</script>";
}
exit();
}