PHP - Anyway To Do This Loop?without Repeating..

Hi guys i am a complete novice learning.

I want to automatically load a form page without using the submit button.

i can get the page to load no problems but the url keeps refreshing in the browser window ? here is the code i am using.

<h3>View Mileage.</h3>

		
		<form method="post" action="testmileage.php" name="mileage" id = "mileage">

		
		<input type="hidden" name="start-date" value="2020-04-06">

		
		<input type="hidden" name="end-date" value="2021-04-05">

		
		</form>


<script>window.onload = function(){
  document.mileage.submit();
};</script>

I have a simple problem but seem to be hitting a roadblock with fixing it.

I am in the process of upgrading a site from PHP 5.6 to 7.0 (eventually to 7.2)

I am seeing error notices like

PHP Notice:  Undefined index: productpage in …..

I know this it because the $_REQUEST can sometimes be empty depending on what data is passed back and when certain pages are loaded

$productpage = mysqli_real_escape_string($con, $_REQUEST['productpage']);

I also know that I could turn the error notice off or use isset to check $_REQUEST but I would prefer to use the ?? '' option to fix this issue.

The problem is that when I add the ?? '' option to the above code the problem resolved itself but then moments later the same error on the same line reappeared in the error logs and I cant understand why.

Can someone give me the correct example of where to place ?? '' in the above code so that I can rule out my potentially dodgy code as being the reason the error keeps reappearing.

$firstArray = array(
'row1' => array(
'dates' => array(
'2014-01-01' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-01-02' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-01-03' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-01-04' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-01-05' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-01-06' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-01-07' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
)
),
'row2' => array(
'dates' => array(
'2014-02-01' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-02-02' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-02-03' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-02-04' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-02-05' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-02-06' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-02-07' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-02-08' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
'2014-02-09' => array('key1' => 'value1', 'key2' => 'value2', 'key3' => 'value3', 'key4' => 'value4', 'key5' => 'value5', 'key6' => 'value6', 'key7' => 'value7', 'key8' => 'value8', 'key9' => 'value9', 'key10' => 'value10'),
)
)
);

$placeDataHere = array();
foreach($firstArray as $key => $dates) {
foreach($dates as $date => $values) {
foreach($values as $key => $value) {
$placeDataHere['DV_' . $date]['SM_' . $key] = 'KS_' . $value;
//Followed by another ~50-70 lines of processing the 3 loop's data..
...
...
....
....
....
....
....
....
}
}
}