sql message Table 'testowanie.id' doesn't exist

I have a problem with me code, i wanted to do that when i click on a checkbox and then on the acceptation button some informations will be inserted into my sql database. There is my code:

<form action="checkboxes.php" method="post">
<input type="checkbox" name="chk1"> 4K </input>
<input type="submit" name="Submit" value="Submit"></input>
</form>

<?php
/* Database connection */

$sDbHost = 'localhost';
$sDbName = 'testowanie';
$sDbUser = 'root';
$sDbPwd = '';
$Conn = mysql_connect ($sDbHost, $sDbUser, $sDbPwd);
mysql_select_db ($sDbName, $Conn)

$checkbox1 = $_POST['chk1'];
if ($_POST["Submit"]=="Submit") {
for ($i=0; $i<sizeof($checkbox1); $i++) {
$query="INSERT INTO cena (name) VALUES ('".$checkbox1[$i]."')";
mysql_query($query) or die (mysql_error() );
  }  
echo "Record is inserted";
}
?>

But when i click on the button this don't work and a text appears "Table 'testowanie.cena' doesn't exist" but the problem is that the table really exist.enter image description here

So if someone can help me it will be great. Thanks,