$sql = "UPDATE users SET ? = ? WHERE user_id = ?";
$stmt = $db->prepare($sql);
$stmt->bind_param("ssi", $obj->{'property'}, $obj->{'value'}, $id);
It says "Fatal error: Call to a member function bind_param() on boolean"
$obj->{'property'} and $obj->{'value'} are strings. $id is int.
What I am doing wrong?