Problem with to_excel helper under CI 2.1.0

[eluser]Ornis[/eluser]
I used to_excel helper (plugin) several times before. However, with version CI 2.1.0 I get errors running the following code:

Code:

public function excel() {
$this->load->helper('to_excel');
$query = $this->db->get('user');
        to_excel($query,'my_excel');
}

The error msg is:

A PHP Error was encountered

Severity: Notice

Message: Undefined property: stdClass::$Type

Filename: mysql/mysql_result.php

Line Number: 89

Any hints? What do I miss here? Thanks.


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P.S.
Above code runs perfectly after downgrading system folder to CI 2.0