public function testExecute()
{
$commandTester = $this->getCommand(array('--format' => 'csv'));
$display = $commandTester->getDisplay();
$this->assertContains('have_query_cache', $display);
$this->assertContains('innodb_log_buffer_size', $display);
$this->assertContains('max_connections', $display);
$this->assertContains('thread_cache_size', $display);
}