Databases
StackOverflow2013
Postsdbo
PO
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PO
    primarykey
    data
    text
    <p>The behavior you are seeing is the intended (see <a href="https://tools.ietf.org/html/rfc7234" rel="nofollow">RFC7234</a> for more details), specified behavior: </p> <p>All modern browsers will send HTTP requests to the server for every page element displayed, regardless of cache status. This was a design decision made at the request of web services (especially advertising networks) to ensure that HTTP servers were able to maintain records of every display of every element. </p> <p>If the browsers did not make these requests, the server would never be notified that an image had been displayed to the user. For advertising networks, this would be catastrophic. Early on, advertising networks 'hacked' their way around this by serving the same ad image using randomly generated names (ex: 'coke_ad_1_98719283719283.gif'). However, for ISPs this practice caused a huge increase in data transfers, because every one of their users was re-downloading these identical ad images, bypassing any caching/proxy servers their ISP was operating.</p> <p>So a truce was reached: Browsers would always send HTTP requests, even for un-expired cached elements. Servers would respond with HTTP 304 status codes ("not modified"). This allows the servers to record the fact that the image was displayed to the client. As a result, advertising networks <em>generally</em> stopped using randomized image names to bypass network cache servers.</p> <p>This gave the ad networks what they wanted - a record of every image displayed - and it gave ISPs what they wanted - cache-able images and static content.</p> <p>That is why there isn't much you can do to prevent browsers from sending HTTP requests for cached page elements.</p> <p>But if you look at other available client-side solutions that came along with html5, there is a scope to prevent resource loading</p> <ol> <li><a href="http://www.html5rocks.com/en/tutorials/appcache/beginner/" rel="nofollow">Cache Manifest</a> (in spite of its gotchas)</li> <li><a href="https://developer.mozilla.org/en-US/docs/Web/API/IndexedDB_API" rel="nofollow">IndexedDB</a> (nice asynchronous features, allows blob storage)</li> <li><a href="https://developer.mozilla.org/en/docs/Web/API/Window/localStorage" rel="nofollow">Local Storage</a> (not async)</li> </ol>
    singulars
    1. This table or related slice is empty.
    1. POStop browser to make HTTP requests for images that should stay cached - mod_expires
      singulars
      1. PTQuestion
    1. PTAnswer
    1. USDDM
    1. USJason Buberel
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTDownMod
    2. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. PO
      1. This table or related slice is empty.
      1. VTUpMod
    1. COI receive 200 OK (see the screenshots in my question) and NOT 304! I know browsers would normally receive 304 "not modified", it's what you recive back when you do NOT use `Cache-Control: max-age=...`. But I'm using `Cache-Control: max-age=...` and the ALL point of using it, is to NOT inquire the server...
      singulars
      1. PO
      1. USMarco Demaio
    2. CO...What surprised me is that the server seemed to be inquired anyway, replying with 200 OK. But as explained by Peter Lundsby (and according to this http://stackoverflow.com/questions/6797361/ ) it's probably just FireBug showing the request, but the request is made to the browser CACHE and not really to the server, that's why is shown in grey color.
      singulars
      1. PO
      1. USMarco Demaio
    3. COJason, do you have any references to additional info? — This was very interesting, I was looking for something like this.
      singulars
      1. PO
      1. USKajMagnus
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload