How to fetch posts that are stored in the different table than (default) wp_posts?

Question

What I need is altering default Wordpress posts-pooling mechanism so I can get posts from other tables in database, not just default wp_posts and wp_postmeta.

How is that possible?

I'm ready to proudly die dealing with consequences of altering Wordpress core.

Answer 1

Don't hack the Core. There are filters in WP_Query that should more than suffice to include your table, if your SQL and regex are good enough.

• posts_distinct - Alters SQL 'DISTINCTROW' clause to the query that returns the post array.
• posts_groupby - Alters SQL 'GROUP BY' clause of the query that returns the post array.
• posts_join - Alters SQL 'JOIN' clause of the query that returns the post array.
• post_limits - Alters SQL 'LIMIT' clause of the query that returns the post array.
• posts_orderby - Alters SQL 'ORDER BY' clause of the query that returns the post array.
• posts_where - Alters SQL 'WHERE' clause of the query that returns the post array.
• posts_join_paged - Alters SQL paging for posts using 'JOIN' clause of the query that returns the post array.
• posts_where_paged - Alters SQL paging for posts using 'WHERE' clause of the query that returns the post array.
• posts_clauses - Alters all the SQL clauses above in one go. It gives you an array of elements that are easy to alter

http://codex.wordpress.org/Class_Reference/WP_Query#Filters

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