[solved] No 'MONTH(date_field)' in $this->db->where(); possible?

[eluser]Jan_1[/eluser]
Thanks a lot, Armchair Samurai!
So,... :
A) I'm not able to put a FALSE to the arguments in the WHERE-Array
B) Everyone of my queries needs a FROM-Information

Code:

function get_ks_summen()
    {
      $wg_id = 34; //short version. normaly done by a sql-query
      $db = "ks_buchung";
      $select = array('COUNT(ks_betrag) AS anzahl','SUM(ks_betrag) AS summe');
// query 1 (this year)
      $this->db->select($select);
      $this->db->where('wg_id', $wg_id);
      $this->db->where('YEAR(ks_datum)','YEAR(CURDATE())', FALSE);
      $this->db->from($db);
      $query1 = $this->db->get(); if ($query1->num_rows() > 0) { $row1 = $query1->row(); }
      $summe_jahr = $row1->summe;
      $anzahl_jahr = $row1->anzahl;
//query 2 (this month)
      $this->db->select($select);
      $this->db->where('wg_id', $wg_id);
      $this->db->where('MONTH(ks_datum)','MONTH(CURDATE())', FALSE);
      $this->db->from($db);
      $query2 = $this->db->get(); if ($query2->num_rows() > 0) { $row2 = $query2->row(); }
      $dieser_monat = $row2->summe;
      $anzahl_dieser = $row2->anzahl;
// query 3 (last month)
      $this->db->select($select);
      $this->db->where('wg_id', $wg_id);
      $this->db->where('MONTH(ks_datum)','MONTH(SUBDATE(CURDATE(), INTERVAL 1 MONTH))', FALSE);
      $this->db->from($db);
      $query3 = $this->db->get(); if ($query3->num_rows() > 0) { $row3 = $query3->row(); }
      $letzter_monat = $row3->summe;
      $anzahl_letzter = $row3->anzahl;

      $data = array(
                    'summe_jahr' => $summe_jahr,
                    'dieser_monat' => $dieser_monat,
                    'letzter_monat' => $letzter_monat,
                    'anzahl_jahr' => $anzahl_jahr,
                    'anzahl_dieser' => $anzahl_dieser,
                    'anzahl_letzter' => $anzahl_letzter
                   );
      return $data;
    }

If somebody finds out how to bring FALSE-Argument in an Where-Array pleeeaase contact me.