title: firebase startAt + equalTo
body: <p>Can you combine <code>startAt</code> and <code>equalTo</code> when there is entity like <code>timestamp_item</code>?</p>
  
  <p>That is, lets say we have <code>1234567_itemA</code> and <code>1234567_itemB</code> and if i want to query only <code>itemA</code> data i'm still receiving both items. </p>
  
  <p>Trying to filter it out with  <code>database().ref('items').orderByChild('timestamp_item').startAt('10000_itemA').limitToLast(10)</code></p>
  
  <p><strong>EDIT (fixed)</strong>: had to change query into <code>(...).orderByChild('timestamp_item').startAt('10000_itemA').endAt('20000_itemA').limitToLast(10)</code></p>