How to change this code from mysqli to PDO - php

Question

if (isset($_GET['page_no']) && $_GET['page_no']!="") {
$page_no = $_GET['page_no'];
} else {
$page_no = 1;
}
$total_records_per_page = 9;
$offset = ($page_no-1) * $total_records_per_page;
$previous_page = $page_no - 1;
$next_page = $page_no + 1;
$adjacents = "2";
$result_count = mysqli_query($con,"SELECT COUNT(*) As total_records FROM `products`");
$total_records = mysqli_fetch_array($result_count);
$total_records = $total_records['total_records'];
$total_no_of_pages = ceil($total_records / $total_records_per_page);
$second_last = $total_no_of_pages - 1; // total page minus 1
$result = mysqli_query($con,"SELECT * FROM `products` LIMIT $offset, $total_records_per_page");
while($row = mysqli_fetch_array($result)){
echo "<tr>
<td>".$row['productCode']."</td>
<td>".$row['productName']."</td>
<td>".$row['MSRP']."</td>
<td><button type='submit' class='buy'>Buy Now</button></td>
</tr>";
}
mysqli_close($con);
?>
I need to change this code to PDO format. And I am not really sure what is the same function of mysqli_fetch_array in PDO.

Answer 1

This is how you would do it:
// Execute query and fetch a single cell from the result
$total_records = $PDO->query('SELECT COUNT(*) FROM `products`')->fetch(PDO::FETCH_COLUMN);
$total_no_of_pages = ceil($total_records / $total_records_per_page);
$second_last = $total_no_of_pages - 1; // total page minus 1
// prepare a statement with 2 parameters and execute it
$stmt = $PDO->prepare('SELECT * FROM `products` LIMIT ?,?');
$stmt->execute([$offset, $total_records_per_page]);
// PDO results are easily traversable
foreach ($stmt->fetchAll() as $row) {
echo "<tr>
<td>".$row['productCode']."</td>
<td>".$row['productName']."</td>
<td>".$row['MSRP']."</td>
<td><button type='submit' class='buy'>Buy Now</button></td>
</tr>";
}
I replaced your concatenated query with a prepared statement, which you should always do!
About fetching: You can traverse the records one by one or fetch all of them like I did into an array and foreach on them. There is many different ways to do it. Always remember about many PDO fetch options available: https://phpdelusions.net/pdo#fetchall