title: Fastest way to check key exists in redis - php
body: <p>Is there any other faster way than <code>EXISTS</code>, to check if a key exists in redis or not? </p>
  
  <p>My problem is, I have over 1 million records in redis and I need to do a key_exists check. This should happen within 10ms.</p>
  
  <p>Any Ideas around this?</p>