Can cache save a page with missing data or functionality from previous visit?

Anonymous May 10, 2014

I have had an issue using a website that has an edit button that has “disappeared” twice while appearing subsequently both prior and post. I made a complaint to the company in question and was told to clear my cache. My understanding of cache was that it was a snapshot of the previously viewed page and not a new or altered page. My question is “Can cache save a page with missing data or functionality from previous visit?”

  1. Oron J
    May 10, 2014 at 12:36 pm

    The answer is yes. A browser's cache is a copy the files previously downloaded. A single web page is made of many files, and normally they will all be in the cache. If a page has been updated in any way, the cache should only supply the elements that have not changed, but there are many reasons why (and how) it might not work properly. The problem you describe is consistent with such a website/cache problem. If clearing the cache does not help, you will have learned something from that too, namely, that in this case the problem lies elsewhere.

    • Dev81961
      May 10, 2014 at 1:07 pm

      Thanks for the reply, much appreciated. I hope I explained myself but just to clarify, the edit button in question was there the first visit, not there on the second occassion, then it appeared again, disappeared and re-appeared without me refreshing the page on any occasion, can this still be a cache issue?

    • Oron J
      May 10, 2014 at 7:00 pm

      I understand that the behaviour of the page is inconsistent. While I can't be certain that this was caused by a corrupt cache (or more accurately, by a conflict between the cache & the server copies), it is possible.
      Emptying the cache is a bit like "switch your computer off and on again". It sounds like hokum, but it makes a lot of sense, since it removes one possible cause of the problem from the list, and may even resolve it. In other words, if the problem doesn't go away, you'll know it wasn't the cache...