Miscellany

$sql = "(SELECT h.*, n.* FROM {task_hierarchy} h 
INNER JOIN {node_revisions} n
ON n.nid = h.nid
INNER JOIN {task} t
ON t.nid = h.nid
WHERE h.project = %d)
UNION (SELECT h.is_project
FROM {task_hierarchy} h
WHERE h.nid = %d)";