Conditional Logic on MySQL Query with PHP

I am doinga MySQL query to retreive data using PHP. I need to have a logic that if the data set returned is empty it shows a warning message else it displays the results:

$searchQuery = mysql_escape_string($_POST['searchQuery']);

$sql="SELECT * FROM db.tblname WHERE column1 = '".$searchQuery."'";

$result = mysqli_query($conn,$sql);

while($row = mysqli_fetch_array($result)){
  echo $row["column1"];
}

mysqli_close($conn);