=== modified file 'includes/actions.inc'
--- includes/actions.inc	2008-12-20 05:20:20 +0000
+++ includes/actions.inc	2009-01-08 15:23:10 +0000
@@ -325,7 +325,7 @@ function actions_save($function, $type, 
   // aid is the callback for singleton actions so we need to keep a separate
   // table for numeric aids.
   if (!$aid) {
-    $aid = db_insert('actions_aid')->useDefaults(array('aid'))->execute();
+    $aid = db_next_id('actions');
   }
 
   db_merge('actions')

=== modified file 'includes/database/database.inc'
--- includes/database/database.inc	2008-12-30 20:27:24 +0000
+++ includes/database/database.inc	2009-01-08 15:32:37 +0000
@@ -818,6 +818,23 @@ abstract class DatabaseConnection extend
    *   The extra handling directives for the specified operator, or NULL.
    */
   abstract public function mapConditionOperator($operator);
+
+  /**
+   * Retrieves an unique id from a given sequence.
+   *
+   * Use this function if for some reason you can't use a serial field,
+   * normally a serial field with db_last_insert_id is preferred.
+   *
+   * @param $sequence
+   *   The name of the sequence.
+   * @return
+   *   An integer number larger than any number returned by earlier calls
+   *   to this function with the same sequence argument.
+   */
+  public function nextId($sequence) {
+    // In the degenerate case every id comes from a single source.
+    return db_insert('sequences')->useDefaults(array('sid'))->execute();
+  }
 }
 
 /**
@@ -1871,6 +1888,22 @@ function db_driver() {
 }
 
 /**
+ * Retrieves an unique id from a given sequence. Use db_last_insert_id is preferred.
+ *
+ * Use this function if for some reason you can't use a serial field,
+ * normally a serial field with db_last_insert_id is preferred.
+ *
+ * @param $sequence
+ *   The name of the sequence.
+ * @return
+ *   An integer number larger than any number returned before for this
+ *   sequence.
+ */
+function db_next_id($sequence) {
+  return Database::getActiveConnection()->nextId($sequence);
+}
+
+/**
  * @} End of "defgroup database".
  */
 

=== modified file 'modules/simpletest/simpletest.install'
--- modules/simpletest/simpletest.install	2008-11-15 13:01:04 +0000
+++ modules/simpletest/simpletest.install	2009-01-08 15:17:46 +0000
@@ -197,17 +197,5 @@ function simpletest_schema() {
       'reporter' => array('test_class', 'message_id'),
     ),
   );
-  $schema['simpletest_test_id'] = array(
-    'description' => 'Stores simpletest test IDs, used to auto-incrament the test ID so that a fresh test ID is used.',
-    'fields' => array(
-      'test_id'  => array(
-        'type' => 'serial',
-        'not null' => TRUE,
-        'description' => 'Primary Key: Unique simpletest ID used to group test results together. Each time a set of tests
-                            are run a new test ID is used.',
-      ),
-    ),
-    'primary key' => array('test_id'),
-  );
   return $schema;
 }

=== modified file 'modules/simpletest/simpletest.module'
--- modules/simpletest/simpletest.module	2008-12-30 16:43:14 +0000
+++ modules/simpletest/simpletest.module	2009-01-08 15:27:43 +0000
@@ -125,7 +125,6 @@ function simpletest_test_form() {
     // Clear test results.
     if (variable_get('simpletest_clear_results', TRUE)) {
       db_query('DELETE FROM {simpletest} WHERE test_id = %d', $_SESSION['test_id']);
-      db_query('DELETE FROM {simpletest_test_id} WHERE test_id = %d', $_SESSION['test_id']);
     }
     unset($_SESSION['test_id']);
 
@@ -353,7 +352,7 @@ function simpletest_test_form_submit($fo
  */
 function simpletest_run_tests($test_list, $reporter = 'drupal') {
   cache_clear_all();
-  $test_id = db_insert('simpletest_test_id')->useDefaults(array('test_id'))->execute();
+  $test_id = db_next_id('simpletest');
 
   // Get the info for the first test being run.
   $first_test = array_shift($test_list);
@@ -527,8 +526,7 @@ function simpletest_clean_database() {
   $schema = drupal_get_schema_unprocessed('simpletest');
   $ret = array();
   foreach (array_diff_key($tables, $schema) as $table) {
-    // Strip the prefix and skip tables without digits following "simpletest",
-    // e.g. {simpletest_test_id}.
+    // Strip the prefix and skip tables without digits following "simpletest".
     if (preg_match('/simpletest\d+.*/', $table, $matches)) {
       db_drop_table($ret, $matches[0]);
     }
@@ -590,12 +588,9 @@ function simpletest_clean_temporary_dire
  */
 function simpletest_clean_results_table() {
   if (variable_get('simpletest_clear_results', TRUE)) {
-    $count = db_result(db_query('SELECT COUNT(test_id) FROM {simpletest_test_id}'));
-
     // Clear test results.
     db_query('DELETE FROM {simpletest}');
-    db_query('DELETE FROM {simpletest_test_id}');
 
-    drupal_set_message(t('Removed @count test results.', array('@count' => $count)));
+    drupal_set_message(t('Removed @count test results.', array('@count' => db_affected_rows())));
   }
 }

=== modified file 'modules/system/system.install'
--- modules/system/system.install	2008-12-30 16:43:14 +0000
+++ modules/system/system.install	2009-01-08 15:17:23 +0000
@@ -474,19 +474,6 @@ function system_schema() {
     'primary key' => array('aid'),
   );
 
-  $schema['actions_aid'] = array(
-    'description' => 'Stores action IDs for non-default actions.',
-    'fields' => array(
-      'aid' => array(
-        'description' => 'Primary Key: Unique actions ID.',
-        'type' => 'serial',
-        'unsigned' => TRUE,
-        'not null' => TRUE,
-      ),
-    ),
-    'primary key' => array('aid'),
-  );
-
   $schema['batch'] = array(
     'description' => 'Stores details about batches (processes that run in multiple HTTP requests).',
     'fields' => array(
@@ -1111,6 +1098,19 @@ function system_schema() {
     'primary key' => array('filename'),
   );
 
+  $schema['sequences'] = array(
+    'description' => 'Stores IDs.',
+    'fields' => array(
+      'sid' => array(
+        'description' => 'Primary Key: Unique ID.',
+        'type' => 'serial',
+        'unsigned' => TRUE,
+        'not null' => TRUE,
+      ),
+    ),
+    'primary key' => array('sid'),
+  );
+
   $schema['sessions'] = array(
     'description' => "Drupal's session handlers read and write into the sessions table. Each record represents a user session, either anonymous or authenticated.",
     'fields' => array(
@@ -3165,6 +3165,14 @@ function system_update_7016() {
   return $ret;
 }
 
+
+function system_update_7017() {
+  $ret = array();
+  db_drop_primary_key($ret, 'actions_aid');
+  db_change_field($ret, 'actions_aid', 'aid', 'sid', array('type' => 'serial', 'unsigned' => TRUE, 'not null' => TRUE), array('primary key' => array('sid')));
+  db_rename_table($ret, 'actions_aid', 'sequences');
+}
+
 /**
  * @} End of "defgroup updates-6.x-to-7.x"
  * The next series of updates should start at 8000.