title: Spring data redis key expiration
body: <p>In spring data redis we have two variables.</p>
  
  <pre><code>RedisTemplate&lt;Key, Value&gt; redisTemplate;
  </code></pre>
  
  <pre><code>HashOperations&lt;Key, HashKey, HashValue&gt; hashOperations;
  </code></pre>
  
  <p>There is a method expireAt(String key, Date date) inside RedisTemplate. So if I want to set an expiry for a particular hash key I can use this method or this only works at Key level and expires all the entries inside that key?</p>