public function testCalculation()
{
$options = array('type' => 'read', 'model' => $this->_model);
$this->_db->return['_execute'] = new MockResult(array('records' => array(array(23))));
$expected = 23;
$result = $this->_db->calculation('count', new Query($options), $options);
$this->assertEqual($expected, $result);
$expected = 'SELECT COUNT(*) as count FROM {mock_database_posts} AS {MockDatabasePost};';
$result = $this->_db->sql;
$this->assertEqual($expected, $result);
$this->_db->return['_execute'] = new MockResult(array('records' => array()));
$result = $this->_db->calculation('count', new Query($options), $options);
$this->assertNull($result);
}