diff -wrU3 a/sites/all/modules/votingapi/votingapi.install b/sites/all/modules/votingapi/votingapi.install
--- a/sites/all/modules/votingapi/votingapi.install	2007-06-29 16:41:56.000000000 -0400
+++ b/sites/all/modules/votingapi/votingapi.install	2008-06-03 18:23:29.000000000 -0400
@@ -271,6 +271,29 @@
   return $ret;
 }
 
+/**
+ * Improve indexing on MySQL.
+ */
+
+function votingapi_update_10() {
+  $ret = array();
+  switch ($GLOBALS['db_type']) {
+    case 'mysql':
+    case 'mysqli':
+      $ret[] = update_sql("ALTER TABLE {votingapi_vote} ADD KEY (tag);");
+      $ret[] = update_sql("ALTER TABLE {votingapi_vote} ADD KEY (content_type, tag);");
+      $ret[] = update_sql("ALTER TABLE {votingapi_vote} ADD KEY (content_type, value_type);");
+
+      $ret[] = update_sql("ALTER TABLE {votingapi_cache} ADD KEY (content_type, function);");
+      $ret[] = update_sql("ALTER TABLE {votingapi_cache} ADD KEY (content_type, tag);");
+      $ret[] = update_sql("ALTER TABLE {votingapi_cache} ADD KEY (content_type, value_type);");
+
+      break;
+  }
+
+  return $ret;
+}
+
 function votingapi_uninstall() {
   db_query("DROP TABLE {votingapi_vote}");
   db_query("DROP TABLE {votingapi_cache}");
diff -wrU3 a/sites/all/modules/votingapi/votingapi_views.inc b/sites/all/modules/votingapi/votingapi_views.inc
--- a/sites/all/modules/votingapi/votingapi_views.inc	2007-06-29 16:41:56.000000000 -0400
+++ b/sites/all/modules/votingapi/votingapi_views.inc	2008-06-03 18:07:41.000000000 -0400
@@ -243,7 +243,7 @@
 function _votingapi_views_values($field = 'tag', $table = 'vote') {
   static $cached;
   if (!isset($cached[$table][$field])) {
-    $results = db_query("SELECT DISTINCT %s FROM {votingapi_%s} WHERE content_type = 'node'", $field, $table);
+    $results = db_query("SELECT %s FROM {votingapi_%s} GROUP BY content_type, %s HAVING content_type = 'node'", $field, $table, $field);
     while ($result = db_fetch_object($results)) {
       $cached[$table][$field][$result->$field] = $result->$field;
     }