I’d like to query post revisions using WP_Query
for display on an admin page, and I want to include pagination parameters.
I have two constraints:
-
I would like to only retrieve revisions for published posts, i.e. revisions whose parent – the post ID for which is given in the post_parent
field – contains publish
in its post_status
field.
-
I would like to ignore the revision autogenerated when a post is published, i.e. the revision whose post_date
matches that of the parent.
Normally I would simply filter these revisions out after getting the array of posts, but I want to display these elements in an admin list table with pagination so I’d like to use WP_Query
‘s support for that.
In SQL, I would use an INNER JOIN like this to grab the parent posts:
SELECT * FROM {$wpdb->posts} AS posts
INNER JOIN {$wpdb->posts} AS parent_posts
ON posts.post_parent = parent_posts.ID
WHERE posts.post_type="revision"
AND parent_posts.post_status="publish"
AND posts.post_date <> parent_posts.post_date
Is this possible to do this using WP_Query
?
You should use posts_join
and posts_where
filters to modify JOIN and WHERE clauses.
add_filter( 'posts_join' , 'se333659_posts_join', 20, 2 );
add_filter( 'posts_where' , 'se333659_posts_where', 20, 2 );
function se333659_posts_join( $join, $query )
{
global $wpdb;
if ( isset($query->query_vars['_rev_of_publ']) &&
$query->query_vars['_rev_of_publ'] == '1' )
{
$join .= " LEFT JOIN {$wpdb->posts} AS rev_p ON ({$wpdb->posts}.post_parent = rev_p.ID) ";
}
return $join;
}
function se333659_posts_where( $where, $query )
{
global $wpdb;
if ( isset($query->query_vars['_rev_of_publ']) &&
$query->query_vars['_rev_of_publ'] == '1' )
{
$where .= ' AND rev_p.post_status = \'publish\' AND '.$wpdb->posts.'.post_date <> rev_p.post_date ';
}
return $where;
}
How to use:
Changes in the query will be made after passing the _rev_of_publ
parameter (name can be changed) to WP_Query
.
$args = [
'post_type' => 'revision',
'post_status' => 'any', // default value is 'publish'
'_rev_of_publ' => 1,
];
$my_query = new WP_Query( $args );
Here you will find more information about using WP_Query
.