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For RSS feeds of multiple categories, is there a way to ensure that a certain number of posts from a particular category always get shown?

• If I want to get feeds from category ID 1, 2, and 3, this works. http://localhost/wordpress/feed/?cat=1%2C2%2C3 That is great. Let's say I have 100 posts from ID 1 and 50 posts from ID 2 and 10 posts from ID 3. The category 1 gets updated almost every day. The category 2 is not that often but gets updated regularly. The category 3 updates occasionally but has very important information. So I'd like to make the feed contain a certain number of posts from category 3 which will be shown always like a sticky thread in a forum. Also some posts of category 2 should be fed as well. I mean I do not want the feed to be occupied with the posts of the category 1. For example, if there are 20 articles in the RSS feed and I want to include at least 4 from the category 3, and 6 articles from the category 2, and 10 from the category 1. Is it possible to do?

• Answer:

  You would have to create a custom feed. That is possible using add_feed function [https://codex.wordpress.org/Rewrite_API/add_feed]. A simple example for usage of this function: [http://resources.mdbitz.com/2010/08/creating-a-custom-feed-in-wordpress/]. The " $posts = query_posts('showposts=5');" line is the key - here you can form an array of posts and sort it in any way you like - just the way you would do if you were building a custom loop for your theme. P.S. You will need to flush rewrite rules once, after adding this to your theme/plugin. You can do that either by visiting Settings>Permalink page in admin area, or by calling flush_rewrite_rules() function. You only need to do this once, not on every load.