Index: modules/dblog/dblog.admin.inc
===================================================================
RCS file: /cvs/drupal/drupal/modules/dblog/dblog.admin.inc,v
retrieving revision 1.8
diff -u -r1.8 dblog.admin.inc
--- modules/dblog/dblog.admin.inc	19 Jul 2008 07:44:45 -0000	1.8
+++ modules/dblog/dblog.admin.inc	19 Dec 2008 16:09:29 -0000
@@ -21,10 +21,30 @@
     '#description' => t('The maximum number of rows to keep in the database log. Older entries will be automatically discarded. (Requires a correctly configured <a href="@cron">cron maintenance task</a>.)', array('@cron' => url('admin/reports/status')))
   );
 
+  $form['dblog_clear'] = array(
+    '#type' => 'fieldset',
+    '#title' => t('Clear database log'),
+    '#description' => t('Remove all entries from the database log.'),
+  );
+
+  $form['dblog_clear']['clear'] = array(
+    '#type' => 'submit',
+    '#value' => t('Clear database log'),
+    '#submit' => array('dblog_clear_log_submit'),
+  );
+
   return system_settings_form($form);
 }
 
 /**
+ * Submit callback: clear database log.
+ */
+function dblog_clear_log_submit(&$form_state, $form) {
+  db_query("DELETE FROM {watchdog}");
+  drupal_set_message(t('Database log cleared.'));
+}
+
+/**
  * Menu callback; displays a listing of log messages.
  */
 function dblog_overview() {