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filter is not described

posts_orderby_request filter-hook . WP 2.5.0

Filters the ORDER BY clause of the query.

For use by caching plugins.

Usage

add_filter( 'posts_orderby_request', 'filter_function_name_1654', 10, 2 );
function filter_function_name_1654( $orderby, $this ){
	// filter...

	return $orderby;
}
$orderby(string)
The ORDER BY clause of the query.
$this(WP_Query)
The WP_Query instance (passed by reference).

Where the hook is called

WP_Query::get_posts()
wp-includes/class-wp-query.php 2655
$orderby = apply_filters_ref_array( 'posts_orderby_request', array( $orderby, &$this ) );

Where the hook is used (in WP core)

Does not used.