title: $this->Agreements->save() - create only one record, why?
body: <p>I need to read all records from table agreements, make changes in filed payments, and update all records, save to table. So, my problem is, that save() only create empty record. Do not update exists record. I show you how:</p>
  
  <p>Reading from table:</p>
  
  <pre><code>$agreements = $this-&gt;Agreement-&gt;find('all');
  $payments = $this-&gt;Payment-&gt;find('all');
  </code></pre>
  
  <p>Manipulation on fields (part of)(example):</p>
  
  <pre><code>$id=0;
  foreach ($agreements as $agreement):
      for ($i=$first_agreement; $i&lt;=$last_agreement; $i++){ 
          if ( $agreement['Agreement']['agreement_number']==$i){
             $agreements[$id]['Agreement']['payment']=$payd[$i];
          }
        }
  $id++;
  endforeach;
  </code></pre>
  
  <p>Writting to table:</p>
  
  <pre><code>$this-&gt;Agreement-&gt;save();
  </code></pre>
  
  <p>A echo debug($agreements) shows correct array, i have tryed also :</p>
  
  <pre><code>$this-&gt;Agreement-&gt;save($agreements);
  </code></pre>
  
  <p>or</p>
  
  <pre><code>$this-&gt;Agreement-&gt;save($this-&gt;request-&gt;data);
  </code></pre>
  
  <p>Can you help/explain me how to write all record?</p>
  
  <p>Cake 2.5.2 PHP : 5.4.4-14</p>