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Source code

function wp_delete_post( $postid = 0, $force_delete = false ) {

	global $wpdb, $wp_rewrite;



	if ( !$post = $wpdb->get_row($wpdb->prepare("SELECT * FROM $wpdb->posts WHERE ID = %d", $postid)) )

		return $post;



	if ( !$force_delete && ( $post->post_type == 'post' || $post->post_type == 'page') && get_post_status( $postid ) != 'trash' && EMPTY_TRASH_DAYS )

			return wp_trash_post($postid);



	if ( $post->post_type == 'attachment' )

		return wp_delete_attachment( $postid, $force_delete );



	do_action('before_delete_post', $postid);



	delete_post_meta($postid,'_wp_trash_meta_status');

	delete_post_meta($postid,'_wp_trash_meta_time');



	wp_delete_object_term_relationships($postid, get_object_taxonomies($post->post_type));



	$parent_data = array( 'post_parent' => $post->post_parent );

	$parent_where = array( 'post_parent' => $postid );



	if ( 'page' == $post->post_type) {

	 	// if the page is defined in option page_on_front or post_for_posts,

		// adjust the corresponding options

		if ( get_option('page_on_front') == $postid ) {

			update_option('show_on_front', 'posts');

			delete_option('page_on_front');

		}

		if ( get_option('page_for_posts') == $postid ) {

			delete_option('page_for_posts');

		}



		// Point children of this page to its parent, also clean the cache of affected children

		$children_query = $wpdb->prepare("SELECT * FROM $wpdb->posts WHERE post_parent = %d AND post_type='page'", $postid);

		$children = $wpdb->get_results($children_query);



		$wpdb->update( $wpdb->posts, $parent_data, $parent_where + array( 'post_type' => 'page' ) );

	} else {

		unstick_post($postid);

	}



	// Do raw query.  wp_get_post_revisions() is filtered

	$revision_ids = $wpdb->get_col( $wpdb->prepare( "SELECT ID FROM $wpdb->posts WHERE post_parent = %d AND post_type = 'revision'", $postid ) );

	// Use wp_delete_post (via wp_delete_post_revision) again.  Ensures any meta/misplaced data gets cleaned up.

	foreach ( $revision_ids as $revision_id )

		wp_delete_post_revision( $revision_id );



	// Point all attachments to this post up one level

	$wpdb->update( $wpdb->posts, $parent_data, $parent_where + array( 'post_type' => 'attachment' ) );



	$comment_ids = $wpdb->get_col( $wpdb->prepare( "SELECT comment_ID FROM $wpdb->comments WHERE comment_post_ID = %d", $postid ));

	if ( ! empty($comment_ids) ) {

		do_action( 'delete_comment', $comment_ids );

		foreach ( $comment_ids as $comment_id )

			wp_delete_comment( $comment_id, true );

		do_action( 'deleted_comment', $comment_ids );

	}



	$post_meta_ids = $wpdb->get_col( $wpdb->prepare( "SELECT meta_id FROM $wpdb->postmeta WHERE post_id = %d ", $postid ));

	if ( !empty($post_meta_ids) ) {

		do_action( 'delete_postmeta', $post_meta_ids );

		$in_post_meta_ids = "'" . implode("', '", $post_meta_ids) . "'";

		$wpdb->query( "DELETE FROM $wpdb->postmeta WHERE meta_id IN($in_post_meta_ids)" );

		do_action( 'deleted_postmeta', $post_meta_ids );

	}



	do_action( 'delete_post', $postid );

	$wpdb->query( $wpdb->prepare( "DELETE FROM $wpdb->posts WHERE ID = %d", $postid ));

	do_action( 'deleted_post', $postid );



	if ( 'page' == $post->post_type ) {

		clean_page_cache($postid);



		foreach ( (array) $children as $child )

			clean_page_cache($child->ID);



		$wp_rewrite->flush_rules(false);

	} else {

		clean_post_cache($postid);

	}



	wp_clear_scheduled_hook('publish_future_post', array( $postid ) );



	do_action('after_delete_post', $postid);



	return $post;

}