如何在Join codeigniter中插入SELECT

How to add sub-query select in $this->join() in Codeigniter? I tried do this such:

 $this->db->join('stocks AS stn', 
 'stn.stocksIdMF = (SELECT b.MedicalFacilitiesIdUser FROM medicalfacilities AS b WHERE 
    b.MedicalFacilitiesIdUser = stn.stocksIdMF AND stn.stocksEndDate >= UNIX_TIMESTAMP()
    ORDER BY stn.stocksId DESC LIMIT 1', 'LEFT');

Full query:

 $this->db->from('medicalfacilities');
        $this->db->join('users', 'users.idUsers = medicalfacilities.MedicalFacilitiesIdUser');
        $this->db->join('medicalfacilities_directions', 'medicalfacilities_directions.id_MF = medicalfacilities.MedicalFacilitiesIdUser', 'LEFT');
        $this->db->join('subscrubetousers su', 'su.SubscrubeToUsersIdNote = medicalfacilities.MedicalFacilitiesIdUser AND su.SubscrubeToUsersType = 9', 'LEFT');
        $this->db->join('thematicspecialization', 'thematicspecialization.idSpecialization = medicalfacilities_directions.id_specialization', 'LEFT');
        $this->db->join('evaluationinstitution ev', 'ev.evaluationinstitutionIdInst = medicalfacilities.MedicalFacilitiesIdUser', 'LEFT');
        $this->db->join('stocks', 'stocks.stocksIdMF = medicalfacilities.MedicalFacilitiesIdUser AND stocks.stocksEndDate >= UNIX_TIMESTAMP()', 'LEFT');
        $this->db->join('commentstomedicalfacilities', 'commentstomedicalfacilities.CommentsToMedicalFacilitiesIdMedical = medicalfacilities.MedicalFacilitiesIdUser', 'LEFT');
        $this->db->join('medicalfacilities_type', 'medicalfacilities_type.idMF = medicalfacilities.MedicalFacilitiesIdUser');
        $this->db->join('typesmedicalfacilities', 'typesmedicalfacilities.type = medicalfacilities_type.type');
        $this->db->join('stocks AS stn', 'stn.stocksIdMF = (SELECT b.MedicalFacilitiesIdUser FROM medicalfacilities AS b WHERE b.MedicalFacilitiesIdUser = stn.stocksIdMF AND stn.stocksEndDate >= UNIX_TIMESTAMP()
        ORDER BY stn.stocksId DESC LIMIT 1)', 'LEFT', FALSE);

Last JOIN do wrong finish query.

Error is:

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'b.MedicalFacilitiesIdUser FROM medicalfacilities AS b WHERE b.MedicalFacilitiesI' at line 12

add a FALSE parameter to the end of your ->join() like this:

$this->db->join('','','', FALSE)

Try this :

$this->db->join('stocks AS stn', 
 'stn.stocksIdMF = (SELECT b.MedicalFacilitiesIdUser FROM medicalfacilities AS b WHERE 
    b.MedicalFacilitiesIdUser = stn.stocksIdMF AND stn.stocksEndDate >= UNIX_TIMESTAMP()
    ORDER BY stn.stocksId DESC LIMIT 1)', 'LEFT', FALSE);