Warning: mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given in $sql? [duplicate]

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• mysqli_fetch_array()/mysqli_fetch_assoc()/mysqli_fetch_row() expects parameter 1 to be resource or mysqli_result, boolean given 33 answers

Please help. I get this errors :

Warning: mysqli_fetch_array() expects parameter 1 to be mysqli_result, boolean given in

This is my php file

<?php 
if($_SERVER['REQUEST_METHOD']=='POST'){

$image = $_POST['image'];
         $name = $_POST['name'];

require_once('dbConnect.php');

$sql ="SELECT id FROM uploads ORDER BY id ASC";

$res = mysqli_query($con,$sql);

$id = 0;

while($row = mysqli_fetch_array($res)){
$id = $row['id'];
}

$path = "uploads/$id.png";

$actualpath = "http://www.fikri.hol.es/$path";

$sql = "INSERT INTO uploads (image,name) VALUES ('$actualpath','$name')";

if(mysqli_query($con,$sql)){
file_put_contents($path,base64_decode($image));
echo "Successfully Uploaded";
}

mysqli_close($con);
}else{
echo "Error";
}

?>

Thanks