title: How to select rows only if column values are same?
body: <p>I have a table like below</p>
  
  <pre><code>City   Status
  a       y
  a       y
  a       y
  b       n
  b       n
  b       y
  c       y
  c       n
  d       n
  d       n
  </code></pre>
  
  <p>I want the result to be returned as</p>
  
  <pre><code>City   Status
  a       y
  a       y
  a       y
  d       n
  d       n
  </code></pre>
  
  <p>Group by city but whose all status value should be same for that city.</p>
  
  <p>How can I do this?</p>