You can delete all post via $wpdb DELETE FROM wp_posts WHERE post_type=”post_type”; DELETE FROM wp_postmeta WHERE post_id NOT IN (SELECT id FROM wp_posts); DELETE FROM wp_term_relationships WHERE object_id NOT IN (SELECT id FROM wp_posts) or use this query replace it with {{your CPT}} with your Custom Post Type DELETE a,b,c FROM wp_posts a LEFT JOIN … Read more
Out of the box, no, posts can’t have parents. They can be assigned to categories, which can be organised hierarchically. Pages, however, can have parents and you can build a menu structure out of them by using that feature. As to where this is enforced: The parent of a post is stored in the column … Read more
I think, not 100% sure that this was the real reason the WP developers took this approach, but common sense tells me that serialize preserves the variable types and have a mini built in error detection, and json stores only string values { key : value }, so when you go back to PHP you … Read more
If you use “IF NOT EXISTS” then the dbdelta script will not upgrade your database with delta’s appeared after the initial creation of the database. (assuming you want to re-use the same sql script) at least… that is what i think
This is a fairly definitive set of responses about transients WPSE: Are transients garbage collected?
@G.M.’s idea to cache the check has lead me to the following helper function. I’ve put it into the global namespace to have it available everywhere. The function doesn’t say anything about the blog status, just if it exists and is not marked as deleted. The database query is very fast (0.0001 seconds) and runs … Read more
global $wpdb; $result = $wpdb->get_results ( ” SELECT * FROM $wpdb->posts WHERE post_type=”page” ” ); foreach ( $result as $page ) { echo $page->ID.'<br/>’; echo $page->post_title.'<br/>’; }
It is mandatory, though it is not enforced. Consider the scenario when two WordPress site has been setup in the same database. One with prefix wp_ and another with wp2_. If you install your plugin in both of the sites with the prefix, your created tables will be wp_liveshoutbox for first site and wp2_liveshoutbox for … Read more
Really no easy way to do what you are wanting to do, but what I would do is make a snapshot of your site, implement yoru changes and if anything brakes restore and try again. It might be down for an hour, but I just recently did this when I somehow bricked a site I … Read more
Menu by itself is a taxonomy in WP. It means that you can find all menus in wp_terms table, by running following query: SELECT * FROM wp_terms AS t LEFT JOIN wp_term_taxonomy AS tt ON tt.term_id = t.term_id WHERE tt.taxonomy = ‘nav_menu’; Menu item is custom post type in WP. They are stored in wp_posts … Read more