-

<?php

// Query code from http://drupalcode.org/project/project.git/blob/refs/heads/7.x-2.x:/usage/includes/pages.inc#l76

  $query = db_select('node', 'n')
    ->fields('n', array('nid', 'title'))
    ->condition('n.nid', $usage_week_nids, 'IN')
    ->condition('n.status', NODE_PUBLISHED)
    ->groupBy('n.nid')
    ->groupBy('n.title')
    ->addTag('node_access');

    $query->addExpression("SUM(DISTINCT p{$i}.count)", "week{$i}");
    $query->leftJoin('project_usage_week_project', "p{$i}", "n.nid = p{$i}.nid AND p{$i}.timestamp = :timestamp{$i}", array(":timestamp{$i}" => $week));

$query
      ->extend('TableSort')
      ->orderByHeader($headers)
      ->extend('PagerDefault')
      ->limit(100)
      ->execute();

/**

SELECT n.nid, n.title, SUM(DISTINCT p1.count) as week1
FROM node n 
LEFT JOIN project_usage_week_project p1 ON n.nid = p1.nid p1.timestamp = (SELECT MAX(timestamp) FROM project_usage_week_project)
WHERE n.status = 1
GROUP BY n.nid, n.title
limit 100
SORT BY week1 DESC
LIMIT 1

**/