public function preDeleteQuery($builder)
{
return "\n //save current version\n static::doBackupRecord(\$this, \$con);\n\n //save workspace_action=deleted\n \$clazz = get_called_class();\n \$updateValues = new \$clazz;\n self::appendWorkspaceInfo(\$updateValues, 'delete');\n\n //update the record\n parent::doUpdate(\$updateValues, \$con);\n\n //move the updated record (marked as deleted) into the version table\n static::doBackupRecord(\$this, \$con);\n ";
}