在CodeIgniter中有类似$ this-> db-> matched_rows（）的东西吗？

I want to update an entry in table or insert if not exist. I am using affected_rows() function but in case if data is unchanged it returns 0 and inserts a duplicate row.

I am using this code,

$datainsert = array(
    "vendor_id"   => $vendor_id,
    "c_date_time" => date('Y-m-d H:i:s')
);
$this->api_vendor_model->update_vendor_login_time($vendor_id, $datainsert);
if ($this->db->affected_rows() == 0) {
    $this->api_vendor_model->insert_vendor_login_time($datainsert);
}

but it does not work in case no rows are affected but an entry exists for vendor_id.

function update_vendor_login_time($vendor_id, $data) {
    $this->db->where('vendor_id', $vendor_id);
    $this->db->update('fa_vendor_login_time', $data);
    $this->error_check(__FUNCTION__);
}

Instead of controller you need to check $this->db->affected_rows() in model file and return TRUE or FALSE. To check duplicate entry your need to check it using select query

MODEL

 function update_vendor_login_time($vendor_id, $data) {
    $q = $this->db->select('id')// add your column nae here
                    ->from('fa_vendor_login_time')
                    ->where(array('vendor_id' => $vendor_id))->get();
    if ($q->num_rows() == 0) {
        $this->db->where('vendor_id', $vendor_id);
        $this->db->update('fa_vendor_login_time', $data);
        $this->error_check(__FUNCTION__);
        if ($this->db->affected_rows() > 0) {
            return TRUE;
        } else {
            return FALSE;
        }
    }else{
        return TRUE;
    }
}

CONTROLER

$insert = $this->api_vendor_model->update_vendor_login_time($vendor_id, $datainsert);
if (!$insert) {

    $this->api_vendor_model->insert_vendor_login_time($datainsert);
}

No, there's no such function.

affected_rows() works that way because that's how the database works - it won't return feedback for rows it didn't actually update. This is outside of the framework's control.