pagination within if not working properly - php

Question

I am building a search page where the user can search by a field and then the table is displayed.I am trying to implement pagination through php in it but the pagination is not working.Any guidelines to paginate will be helpful.I am presenting the code of one if where the user has entered 1st field and the other fields are left blank,there are other condition as well.
if($item!="" && $brand=="" && $model=="") {
$sql ="SELECT * FROM table WHERE Product LIKE '%".$item."%' ";
$result = mysql_query($sql);
//$result1 = mysql_query($sql1);
$r = mysql_fetch_array($result);
$p=$r['Product'];
$b=$r['Brand'];
$m=$r['Model'];
if ($item!=$p) {
echo "<font style=\"color:Red;\"><h3>No Item Found!!!</h3></font>";
} else {
echo "<table class='table table-striped table-bordered bootstrap-datatable datatable'>
<thead>
<tr>
<th>Item</th>
<th>Brand</th>
<th>Model</th>
<th>Dealer Price</th>
<th>Quantity</th>
<th>Description</th>
</tr>
</thead>";
if (!(isset($pagenum))) {
$pagenum = 1;
}
//Here we count the number of results
//Edit $data to be your query
$data = mysql_query("SELECT * FROM table WHERE Product='$item' ") or die(mysql_error());
$rows = mysql_num_rows($data);
//This is the number of results displayed per page
$page_rows = 10;
//This tells us the page number of our last page
$last = ceil($rows/$page_rows);
//this makes sure the page number isn't below one, or more than our maximum pages
if ($pagenum < 1) {
$pagenum = 1;
} elseif ($pagenum > $last) {
$pagenum = $last;
}
//This sets the range to display in our query
$max = 'limit ' .($pagenum - 1) * $page_rows .',' .$page_rows;
$sqll ="SELECT * FROM table WHERE Product='$item' $max ";
$resultt = mysql_query($sqll);
echo "<tbody>";
while($row = mysql_fetch_array($resultt)) {
echo "<tr>";
echo "<td>" . $row['Product'] . "</td>";
echo "<td>" . $row['Brand'] . "</td>";
echo "<td>" . $row['Model'] . "</td>";
echo "<td>" . $row['Dprice'] . "</td>";
echo "<td>" . $row['Quantity'] . "</td>";
echo "<td>" . $row['Quality'] . "</td>";
echo "</tr>";
}
echo "</tbody>";
echo "</table>";
echo " --Page $pagenum of $last-- <p>";
// First we check if we are on page one. If we are then we don't need a link to the previous page or the first page so we do nothing. If we aren't then we generate links to the first page, and to the previous page.
if ($pagenum == 1) {
} else {
echo " <a href='{$_SERVER['PHP_SELF']}?pagenum=1'> <<-First</a> ";
echo " ";
$previous = $pagenum-1;
echo " <a href='{$_SERVER['PHP_SELF']}?pagenum=$previous'> <-Previous</a> ";
}
//just a spacer
echo " ---- ";
//This does the same as above, only checking if we are on the last page, and then generating the Next and Last links
if ($pagenum == $last) {
} else {
$next = $pagenum+1;
echo " <a href='{$_SERVER['PHP_SELF']}?pagenum=$next'>Next -></a> ";
echo " ";
echo " <a href='{$_SERVER['PHP_SELF']}?pagenum=$last'>Last ->></a> ";
}
} elseif($item=="" && $brand!="" && $model=="") {
...so on
I have tried paginating the table,10 rows are visible in the first page,but on going to the next page no table is showing,although there are other data s in the table.

Answer 1

The error is that you must add at the top of first file
$pagenum = filter_input(INPUT_GET, 'pagenum', FILTER_SANITIZE_NUMBER_INT);
You can't access to $pagenum directly without assign it a value from $_GET param.
I hope this is useful!