PHP header not working - php

Question

I have a web page that will get the data using POST method from the other page and then store the data to the database. After it's done, I want it to go back to the page where the data comes from. I used header(). But it didn't work.
Here's my code:
<?php
$date = $_POST['date'];
$spent = $_POST['spent'];
$description = $_POST['description'];
$dbc = mysqli_connect('oniddb.cws.oregonstate.edu', 'chentao-db', 'BUU3UuwwGfwt7hxV', 'chentao-db')
or die(mysql_error());
$query = "SELECT Total FROM Expense E ORDER BY E.Index DESC LIMIT 1";
//get the total
$result = mysqli_query($dbc, $query) or die(mysql_error());
$total = mysqli_fetch_array($result, MYSQL_ASSOC);
$total = $total['Total'] + $spent;
$query = "INSERT INTO Expense (Date, Spent, Total, Description) VALUES ('$date', '$spent', '$total', '$description')";
$result = mysqli_query($dbc, $query) or die(mysql_error());
mysql_close($dbc);
header("Location: fetchData.php");
?>
What's wrong with it? Thank you.

Answer 1

I guess it would work something like this
header("Location: http://".$_SERVER['HTTP_HOST']."/fetchData.php");

Answer 2

try to place
ob_start();
at top of your file..
Or you can try
header('Location: '.$_SERVER['HTTP_REFRER']);
die;
don't forget to place die at last.

Answer 3

If your first query does not return any result, then the execution fails at this line:
$total = $total['Total'] + $spent;
Check if the first query has any results like this:
if(isset($total['Total'])){
$total = $total['Total'] + $spent;
}
else {
$total = $spent;
}