Illuminate\Database\Connection::getSchemaBuilder PHP Method

    public function getSchemaBuilder()
    {
        if (is_null($this->schemaGrammar)) {
            $this->useDefaultSchemaGrammar();
        }
        return new SchemaBuilder($this);
    }

 /**
  * Create a new FieldTypeSchema instance.
  *
  * @param FieldType  $fieldType
  * @param Repository $cache
  */
 public function __construct(FieldType $fieldType, Container $container, Repository $cache)
 {
     $this->cache = $cache;
     $this->container = $container;
     $this->fieldType = $fieldType;
     $this->connection = $container->make('db')->connection();
     $this->schema = $this->connection->getSchemaBuilder();
 }