Error 500 at GET /trade-school/488837

In SQLite3::ResultSet#read the column INFO returned a Nil but a String was expected.

See raw message
                        In SQLite3::ResultSet#read the column INFO returned a Nil but a String was expected.
                
                            84      col_index = next_column_index
                            85      value = read
                            86      if value.is_a?(T)
                            87        value
                            88      else
                            89        raise DB::ColumnTypeMismatchError.new(
                            90          context: "#{self.class}#read",
                            91          column_index: col_index,
                            92          column_name: column_name(col_index),
                            93          column_type: value.class.to_s,
                            94          expected_type: T.to_s
                        
db read
raise DB::ColumnTypeMismatchError.new(
                            682
                            683  # INFO
                            684  DB.open "sqlite3://./IPEDS.db" do |db|
                            685    db.query "SELECT INFO, ADMISSION_INFO FROM CombinedInfo WHERE UNITID = #{unitid}" do |rs|
                            686      rs.each do
                            687        info = rs.read(String)
                            688        admission_info = rs.read(String)
                            689      end
                            690    end
                            691
                            692    # DEGREES
                        
app ->
info = rs.read(String)
                            7    getter method, path, handler
                            8    @handler : HTTP::Server::Context -> String
                            9
                            10    def initialize(@method : String, @path : String, &handler : HTTP::Server::Context -> _)
                            11      @handler = ->(context : HTTP::Server::Context) do
                            12        output = handler.call(context)
                            13        output.is_a?(String) ? output : ""
                            14      end
                            15    end
                            16  end
                            17end
                        
kemal ->
output = handler.call(context)
                            44
                            45    # Processes the route if it's a match. Otherwise renders 404.
                            46    private def process_request(context)
                            47      raise Kemal::Exceptions::RouteNotFound.new(context) unless context.route_found?
                            48      return if context.response.closed?
                            49      content = context.route.handler.call(context)
                            50
                            51      if !Kemal.config.error_handlers.empty? && Kemal.config.error_handlers.has_key?(context.response.status_code)
                            52        raise Kemal::Exceptions::CustomException.new(context)
                            53      end
                            54
                        
kemal process_request
content = context.route.handler.call(context)
                            12      @routes = Radix::Tree(Route).new
                            13      @cached_routes = Hash(String, Radix::Result(Route)).new
                            14    end
                            15
                            16    def call(context : HTTP::Server::Context)
                            17      process_request(context)
                            18    end
                            19
                            20    # Adds a given route to routing tree. As an exception each `GET` route additionaly defines
                            21    # a corresponding `HEAD` route.
                            22    def add_route(method : String, path : String, &handler : HTTP::Server::Context -> _)
                        
kemal call
process_request(context)
                            23
                            24  abstract def call(context : HTTP::Server::Context)
                            25
                            26  def call_next(context : HTTP::Server::Context)
                            27    if next_handler = @next
                            28      next_handler.call(context)
                            29    else
                            30      context.response.respond_with_status(:not_found)
                            31    end
                            32  end
                            33
                        
crystal call_next
next_handler.call(context)
                            8    def initialize
                            9      @routes = Radix::Tree(WebSocket).new
                            10    end
                            11
                            12    def call(context : HTTP::Server::Context)
                            13      return call_next(context) unless context.ws_route_found? && websocket_upgrade_request?(context)
                            14      context.websocket.call(context)
                            15    end
                            16
                            17    def lookup_ws_route(path : String)
                            18      @routes.find "/ws" + path
                        
kemal call
return call_next(context) unless context.ws_route_found? && websocket_upgrade_request?(context)
                            23
                            24  abstract def call(context : HTTP::Server::Context)
                            25
                            26  def call_next(context : HTTP::Server::Context)
                            27    if next_handler = @next
                            28      next_handler.call(context)
                            29    else
                            30      context.response.respond_with_status(:not_found)
                            31    end
                            32  end
                            33
                        
crystal call_next
next_handler.call(context)
                            70          context.response.status_code = 304
                            71          return
                            72        end
                            73        send_file(context, file_path)
                            74      else
                            75        call_next(context)
                            76      end
                            77    end
                            78
                            79    private def modification_time(file_path)
                            80      File.info(file_path).modification_time
                        
kemal call
call_next(context)
                            23
                            24  abstract def call(context : HTTP::Server::Context)
                            25
                            26  def call_next(context : HTTP::Server::Context)
                            27    if next_handler = @next
                            28      next_handler.call(context)
                            29    else
                            30      context.response.respond_with_status(:not_found)
                            31    end
                            32  end
                            33
                        
crystal call_next
next_handler.call(context)
                            3  class ExceptionHandler
                            4    include HTTP::Handler
                            5    INSTANCE = new
                            6
                            7    def call(context : HTTP::Server::Context)
                            8      call_next(context)
                            9    rescue ex : Kemal::Exceptions::RouteNotFound
                            10      call_exception_with_status_code(context, ex, 404)
                            11    rescue ex : Kemal::Exceptions::CustomException
                            12      call_exception_with_status_code(context, ex, context.response.status_code)
                            13    rescue ex : Exception
                        
kemal call
call_next(context)
                            23
                            24  abstract def call(context : HTTP::Server::Context)
                            25
                            26  def call_next(context : HTTP::Server::Context)
                            27    if next_handler = @next
                            28      next_handler.call(context)
                            29    else
                            30      context.response.respond_with_status(:not_found)
                            31    end
                            32  end
                            33
                        
crystal call_next
next_handler.call(context)
                            352  # elapsed_time # => 20.milliseconds (approximately)
                            353  # ```
                            354  def self.measure(&block : ->) : Time::Span
                            355    start = monotonic
                            356    yield
                            357    monotonic - start
                            358  end
                            359
                            360  # Creates a new `Time` instance representing the current time from the
                            361  # system clock observed in *location* (defaults to local time zone).
                            362  def self.local(location : Location = Location.local) : Time
                        
crystal call
monotonic - start
                            23
                            24  abstract def call(context : HTTP::Server::Context)
                            25
                            26  def call_next(context : HTTP::Server::Context)
                            27    if next_handler = @next
                            28      next_handler.call(context)
                            29    else
                            30      context.response.respond_with_status(:not_found)
                            31    end
                            32  end
                            33
                        
crystal call_next
next_handler.call(context)
                            7    INSTANCE = new
                            8
                            9    def call(context : HTTP::Server::Context)
                            10      context.response.headers.add "X-Powered-By", "Kemal" if Kemal.config.powered_by_header
                            11      context.response.content_type = "text/html" unless context.response.headers.has_key?("Content-Type")
                            12      call_next context
                            13    end
                            14  end
                            15end
                        
kemal call
call_next context
                            46        response.version = request.version
                            47        response.headers["Connection"] = "keep-alive" if request.keep_alive?
                            48        context = Context.new(request, response)
                            49
                            50        Log.with_context do
                            51          @handler.call(context)
                            52        rescue ex : ClientError
                            53          Log.debug(exception: ex.cause) { ex.message }
                            54        rescue ex
                            55          Log.error(exception: ex) { "Unhandled exception on HTTP::Handler" }
                            56          unless response.closed?
                        
crystal process
@handler.call(context)
                            510          return
                            511        end
                            512      end
                            513    {% end %}
                            514
                            515    @processor.process(io, io)
                            516  ensure
                            517    {% begin %}
                            518      begin
                            519        io.close
                            520      rescue IO::Error{% unless flag?(:without_openssl) %} | OpenSSL::SSL::Error{% end %}
                        
crystal handle_client
@processor.process(io, io)
                            463          end
                            464
                            465          if io
                            466            # a non nillable version of the closured io
                            467            _io = io
                            468            spawn handle_client(_io)
                            469          else
                            470            break
                            471          end
                            472        end
                            473      ensure
                        
crystal ->
spawn handle_client(_io)
                            141  end
                            142
                            143  # :nodoc:
                            144  def run
                            145    GC.unlock_read
                            146    @proc.call
                            147  rescue ex
                            148    if name = @name
                            149      STDERR.print "Unhandled exception in spawn(name: #{name}): "
                            150    else
                            151      STDERR.print "Unhandled exception in spawn: "
                        
crystal run
@proc.call
                            93        {Pointer(Void).null, Pointer(Void).null}
                            94      {% else %}
                            95        Fiber.stack_pool.checkout
                            96      {% end %}
                            97
                            98    fiber_main = ->(f : Fiber) { f.run }
                            99
                            100    # FIXME: This line shouldn't be necessary (#7975)
                            101    stack_ptr = nil
                            102    {% if flag?(:win32) %}
                            103      # align stack bottom to 16 bytes
                        
crystal ->
fiber_main = ->(f : Fiber) { f.run }
Request info
URI:
localhost:3000/trade-school/488837
Query string:
Headers
Connection
["keep-alive"]
X-Powered-By
["Kemal"]
Content-Type
["text/html"]