Help:Purge

Purge is a function that tells the server to clear its cache for a page. This causes the server to rebuild the page completely, which can be used to update the page in case it is outdated or not showing correctly.

Purging can be used when a template that is being used on a page gets changed. Because the server caches pages for better performance, the page that is using the template may appear to continue showing the old version of the template. This can be fixed by editing the page, which will cause the server to rebuild it when you save the edit. The purge function can be used to achieve the same effect without having to edit the page.

Purging is harmless and you can't break anything by doing it. Purging does require slightly more processing power to complete, though, so don't overuse the purge function.

How to purge

 * Purging usually happens almost immediately, although it may sometimes take a couple of minutes.

Purge request to server

 * 1) At the end of the URL of the page, add the text  . For example, if the URL of the page is , the URL to purge the page would be.
 * 2) Then, simply visit that page by pressing . You will be taken to a confirmation page; just click '' to continue.

You can also simplify the process by doing the following:


 * 1) Click on the  or  tabs at the top of the page.
 * 2) Change the last portion of the URL's query string from   or   to  . If there is anything after that part of the URL, simply remove it.

Using a gadget
You can enable the PurgeTab gadget in your user preferences. This adds a link at the top of the page, or under the "More" menu, that lets you purge the page in one click. You can also enable the UTCLiveClock gadget which displays a clock in the top-right corner; clicking on the clock will also purge the page. You will not be shown a confirmation step when using these two gadgets to purge.

Null edit
While purging should do the trick in most cases, there may be times where purging is not enough. For example, if you added a page to a category, but that page isn't showing up on the category page, purging might not be enough. To fix this problem, you will need to edit the page. You don't actually have to make any changes to the page. All you have to do is:


 * 1) Click on the '' button at the top of the page.
 * 2) Click '' without making any changes.

This is called a null edit. It will tell the server to rebuild the page and update the link tables, so category pages will be updated to show the page, but since you did not actually make any changes to the page content, nothing gets recorded in the page history. If you only add blank lines to the end of the page, the software will ignore those and will also count it as a null edit.

If you do make changes to the page, an edit will be recorded in the page history like normal, but all the other effects of doing a null edit will be applied as well. As such, if you want to make any changes to the page you want to null edit, you can simply edit the page and make those changes without having to do a null edit before or after.

For images
To refresh thumbnails for an image that is being used on a page, you may have to purge both the image description page and the page the image is being used on. If the image is from the Wikimedia Commons, you may need to go to the description page on Commons before purging.

If the thumbnails still do not regenerate successfully, it is probably because the server has cached an error page with the URL of a thumbnail, but the page was not purged because the actual thumbnail doesn't exist. The solution is to request the thumbnail with an unusual URL, say by appending " " to the end, then do a usual purge.