Retrieve info for user lists to prevent multiple queries by get_userdata()

Signature

cache_users( $user_ids )
user_ids
 (array) User ID numbers list

Return

(void)

Source

function cache_users( $user_ids ) {
	global $wpdb;

	$clean = _get_non_cached_ids( $user_ids, 'users' );

	if ( empty( $clean ) )
		return;

	$list = implode( ',', $clean );

	$users = $wpdb->get_results( "SELECT * FROM $wpdb->users WHERE ID IN ($list)" );

	$ids = array();
	foreach ( $users as $user ) {
		update_user_caches( $user );
		$ids[] = $user->ID;
	}
	update_meta_cache( 'user', $ids );
}
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