I'm trying to print a row from a table in mysql using a PHP script - here is the code but its not working - it shows Bad query apparently there is no issue:

$conn = mysqli_connect($servername, $username, $password, $db);
if (!$conn) {
   die("Connection failed: " . mysqli_connect_error());
}

else{

echo "Connected successfully";

}


$any = "show columns from help_category";
$chk = mysqli_query($any) or die("Bad Query: $sql");
echo"<table border='3'>";
echo"<tr><td>Type</td><tr>";

while($row = mysqli_fetch_assoc($chk))

{

echo"<tr><td>{$row['Type']}</td><tr>";


}


echo"</table>";