title: Is there any cache in react-admin
body: <p><strong>General concept of app:</strong> From the admin panel I want to be able to do CRUD operations on following entities: <strong><em>Slider</em></strong> and <strong><em>Banner</em></strong>. <strong><em>Banner</em></strong> can be added to many <strong><em>Sliders</em></strong> and can have different <strong>position</strong> on each. Due to that fact there is a third entity: <strong><em>BannerSlider</em></strong> that consists of <em>banner_id</em>, <em>slider_id</em> and <em>position</em> fields;</p>
  
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  <p><strong>Code:</strong></p>
  
  <pre><code>export const SliderEdit = props =&gt; (
      &lt;Edit {...props}&gt;
          &lt;SimpleForm&gt;
              &lt;NumberInput source="status" /&gt;
              &lt;ArrayInput source="bannerSliders"&gt;
                  &lt;SimpleFormIterator&gt;
                      &lt;ReferenceInput label="Banner" source="banner.id" reference="banners"&gt;
                          &lt;SelectInput optionText="name" /&gt;
                      &lt;/ReferenceInput&gt;
  
                      &lt;NumberInput source="position" /&gt;
                  &lt;/SimpleFormIterator&gt;
              &lt;/ArrayInput&gt;
          &lt;/SimpleForm&gt;
      &lt;/Edit&gt;
  );
  </code></pre>
  
  <hr>
  
  <p><strong>Issue:</strong> When there are 5 banners assigned to given slider, there are 5 requests to backend, each from <code>&lt;ReferenceInput&gt;</code>. Each request is the same request and have same parameters. Is there any way to call the backend only once? Or maybe there is something wrong with my code?</p>
  
  <hr>
  
  <p>Also, as a side note - I think when user clicks "add" there shouldn't be additional request for the new <code>ReferenceInput</code>, cause all the data is already there. But that's something to consider for the authors. ( Yeah, I know I may contribute too :P )</p>