Asserts that a connection ID exists.
integer $id: The connection ID to verify.
protected function assertConnection($id) {
$list = $this->monitor
->query('SHOW PROCESSLIST')
->fetchAllKeyed(0, 0);
return $this
->assertTrue(isset($list[$id]), format_string('Connection ID @id found.', array(
'@id' => $id,
)));
}