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    <p>(hey, everyone: please don't just mindlessly copy&amp;paste all headers you can find)</p> <p>First of all, <a href="http://httpwg.org/specs/rfc7234.html#history.lists" rel="noreferrer">Back button history is <em>not a cache</em></a>:</p> <blockquote> <p>The freshness model (Section 4.2) does not necessarily apply to history mechanisms. That is, a history mechanism can display a previous representation even if it has expired.</p> </blockquote> <p>In the old HTTP spec the wording was even stronger, explicitly telling browsers to disregard cache directives for back button history.</p> <p>Back is supposed to go back in time (to the time when the user <em>was</em> logged in). It does not navigate forward to a previously opened URL.</p> <p>However, in practice, the cache can influence the back button, in very specific circumstances:</p> <ul> <li>Page <em>must</em> be delivered over <strong>HTTPS</strong>, otherwise this cache-busting won't be reliable. Plus, if you're not using HTTPS, then your page is vulnerable to login stealing in many other ways.</li> <li>You must send <code>Cache-Control: no-store, must-revalidate</code> (some browsers observe <code>no-store</code> and some observe <code>must-revalidate</code>)</li> </ul> <p>You <em>never</em> need any of:</p> <ul> <li><code>&lt;meta&gt;</code> with cache headers — it doesn't work at all. Totally useless.</li> <li><code>post-check</code>/<code>pre-check</code> — it's IE-only directive that only applies to <em>cachable</em> resources.</li> <li>Sending same header twice or in dozen parts. Some PHP snippets out there actually replace previous headers, resulting in only last one being sent.</li> </ul> <p>If you want, you could add:</p> <ul> <li><code>no-cache</code> or <code>max-age=0</code>, which will make resource (URL) "stale" and require browsers to check with the server if there's a newer version (<code>no-store</code> already implies this even stronger).</li> <li><code>Expires</code> with a date in the past for HTTP/1.0 clients (although <em>real</em> HTTP/1.0-only clients are completely non-existent these days).</li> </ul> <hr> <p>Bonus: <a href="http://httpwg.org/specs/rfc7234.html" rel="noreferrer">The new HTTP caching RFC</a>.</p>
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    1. POHow to control web page caching, across all browsers?
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    1. COwill this have any side-effect on the performance of the website in terms of loading time ? how no-store , no-cache , must-revalidate affect performance ?
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      1. USRaman Ghai
    2. CO@RamanGhai Disabling cache generally hurts performance (and all 3 options you've mentioned disable caching). It may make CDNs and ISP proxies (e.g. commonly used by mobile operators) ineffective. It doesn't hurt first load by a new user (aside from the proxy issue), but then subsequent navigation may be a lot slower.
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    3. CO@porneL you state that we must send `Cache-Control: must-revalidate`. Why not send `Cache-Control: no-cache` since `no-cache` already implies `must-revalidate`? http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9.1
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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.

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