如何使用CakePHP在不同的表上保存数据？

I have 3 tables named places, images and place_images. I want to save the IDs of table images and places to the table place_images. I am using CakePHP as my framework.

I am new to PHP programing and Cake framework.

Here is my code which saves the images:

for($img = 0; $img < count($this->request->data['Place']['img']); $img++){
    $file = $this->request->data['Place']['img'];
    if ($file[$img]['tmp_name']) {
        if ($file[$img]['error'] === UPLOAD_ERR_OK) {
            $new_file = $s3place->upload($file[$img]['tmp_name']);
            $image_data = array(
                'filename' => $new_file,
                'metadata' => '',
                'title' => $this->request->data['Place']['img_title'][$img],
                'description' => $this->request->data['Place']['img_desc'][$img],
                'thumb_ready' => 1
            );
            //pr($image_data). exit;
            if (UserPerm::places_attribute()) {
                $image_data['source_url'] = $this->request->data['Place']['img_source'][$img];
                $image_data['source_name'] = $this->request->data['Place']['img_source_name'][$img];
            }

            App::uses('Image', 'model');
            $Image = new Image();
            $is_new_file = false;
            if (isset($old_data['Image']['id']) && $old_data['Image']['id']) {
                $image_data['id'] = $old_data['Image']['id'];
                $Image->id = $old_data['Image']['id'];
            } else {
                $Image->create();
                $is_new_file = true;
            }

            if ($Image->save($image_data)) {
                if ($is_new_file) {
                    $this->request->data['Place']['image_id'] = $Image->getLastInsertID();
                } else {
                    $this->request->data['Place']['image_id'] = $old_data['Image']['id'];
                }

            // Delete old image in S3
            /*if (isset($old_data['Image']['id']) && $old_data['Image']['id']) {
                  $s3place->del($old_data['Image']['filename']);
              } */
            } else {
                $this->Session->setFlash(__('The image could not be saved. Please, try again.') . $err, 'flash_error');
                return;
            }
     } else {
         $this->Session->setFlash(__('The image could not be uploaded. Please, try again.') . $err, 'flash_error');
         return;
     }
}} // end for loop

This is covered in detail in the CakePHP book under [Associations: Linking Models Together] - specifically the part on [Has and Belongs To Many]

Once your associations are set up correctly, and you're saving per the book's instructions, it will save all the fields automatically.