This is my php code to update products in database:

```php
$sql="UPDATE product SET name=$newname , price=$price , stock=$stock , color=$color WHERE id=$id";
if($conn->query($sql)){
    echo "product update";
}

```

It gives this error:

```
Error: UPDATE product SET name=samsung galaxy note 20 ultra , price=40000 , stock=5 , color=white WHERE id=1
You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'galaxy note 20 ultra , price=40000 , stock=5 , color=white WHERE id=1' at line 1

```