/**
  * Create a new query builder instance.
  *
  * @param  \Illuminate\Database\ConnectionInterface  $connection
  * @param  \Illuminate\Database\Query\Grammars\Grammar  $grammar
  * @param  \Illuminate\Database\Query\Processors\Processor  $processor
  * @return void
  */
 public function __construct(ConnectionInterface $connection, Grammar $grammar = null, Processor $processor = null)
 {
     $this->connection = $connection;
     $this->grammar = $grammar ?: $connection->getQueryGrammar();
     $this->processor = $processor ?: $connection->getPostProcessor();
 }