title: deleting database cache after some time codeigniter
body: <p>I was wondering if there is any workaround to delete <code>database cache</code> in codeigniter, say after every 5 hours. by default <code>database query cache</code> is persistent and we have to delete it manually. </p>
  
  <p>Can we make <code>db cache</code> work like <code>page level cache</code> in CI, where we can specify time for cache!</p>