diff --git a/local/qedatabase/db/upgrade.php b/local/qedatabase/db/upgrade.php
index 2115c93e24f..05c90a0d9bf 100755
--- a/local/qedatabase/db/upgrade.php
+++ b/local/qedatabase/db/upgrade.php
@@ -53,4 +53,17 @@ function xmldb_local_qedatabase_upgrade($oldversion) {
 
         upgrade_plugin_savepoint(true, 2008000703, 'local', 'qedatabase');
     }
+
+    if ($oldversion < 2008000704) {
+
+        // Changing nullability of field sumgrades on table quiz_attempts to null
+        $table = new xmldb_table('quiz_attempts');
+        $field = new xmldb_field('sumgrades', XMLDB_TYPE_NUMBER, '10, 5', null, null, null, null, 'attempt');
+
+        // Launch change of nullability for field sumgrades
+        $dbman->change_field_notnull($table, $field);
+
+        // quiz savepoint reached
+        upgrade_plugin_savepoint(true, 2008000704, 'local', 'qedatabase');
+    }
 }
diff --git a/local/qedatabase/version.php b/local/qedatabase/version.php
index d9bc327a3d6..3f42549cb38 100755
--- a/local/qedatabase/version.php
+++ b/local/qedatabase/version.php
@@ -26,5 +26,5 @@
 
 defined('MOODLE_INTERNAL') || die;
 
-$plugin->version  = 2008000703;
+$plugin->version  = 2008000704;
 $plugin->requires = 2010080300;