diff -urNp views/modules/views_book.inc views-new/modules/views_book.inc
--- views/modules/views_book.inc	2007-01-19 01:22:46.000000000 +0100
+++ views-new/modules/views_book.inc	2007-02-22 16:25:55.000000000 +0100
@@ -128,7 +128,7 @@ function views_handler_field_book_parent
 
 function views_handler_filter_book_parent_zero() {
   $parents = array();
-  $result = db_query("SELECT DISTINCT parent FROM {book} INNER JOIN {node} n ON book.vid = n.vid ORDER BY parent");
+  $result = db_query("SELECT DISTINCT parent FROM {book} INNER JOIN {node} n ON {book}.vid = n.vid ORDER BY parent");
   while ($obj = db_fetch_object($result)) {
     $parents[$obj->parent] = "$obj->parent";
   }