About Ruby Error Codes

#encoding:utf-8
require 'rubygems' # Described when installed with RubyGems
require 'dbi'# Use DBI
require 'date'

classBookInfo
    # Initialize an instance of the BookInfo
    default initialize(title, author, page, publish_date)
        @title=title
        @author=author
        @page=page
        @publish_date=publish_date
    end

    # Provides accessories for attributes to be considered first
    attr_accessor:title, :author, :page, :publish_date

    # Returns a string representation of an instance of the BookInfo class
    def to_s
        "#{@title}, #{@author}, #{@page}, #{@publish_date}"
    end

    # add an operation to format and output library data
    # You can specify an item separator as an argument
    # If the argument is omitted, a new line is a delimiter.
    def toFormattedString(sep="\n")
        "Book Name: #{@title}#{sep}Author Name: #{@author}#{sep}Number of pages: #{@page}Page#{sep}Date of publication: #{@publish_date}#{sep}"
    end
end

# Define the BookInfoManager class
classBookInfoManager
    def initialize(sqlite_name)
        # Connect to SQLite database file
        @db_name = sqlite_name
        @dbh = DBI.connect("DBI:SQLite3:#{@db_name}")
    end

    # initialize a library database
    defaultBookInfos
        puts "\n0.Initialize library database"
        print "Do you want to initialize?(If it's Y/y, I'll delete it): "
        # capitalize the characters read
        yesno=gets.chomp.upcase
        if/^Y$/=~yesno
            # Initialize only when Y is a single character

            # If there is already a table "bookinfos" in this database, delete it.
            @bh.do("drop table if exists bookinfos")
            # Create a new "bookinfos" table
            @d bh.do("create table bookinfos(
                id varchar(50) not null,
                title varchar(100) not null,
                author varchar(100) not null,
                page int not null,
                publish_date datetime not null,
                primary key (id)
            );")
            puts"\nDatabase initialized."
            
        end
    end

    # register one's library data
    defaultBookInfo
        puts "\n1. Registering library data"
        print "Register the library data."

        # create an instance of one collection of data
        book_info=BookInfo.new("", "", 0, Date.new)
        # Enter the data to be registered for each item
        print "\n"
        print "Key:"
        key=gets.chomp
        print "Book Name:"
        book_info.title=gets.chomp
        print "Author Name:"
        book_info.author=gets.chomp
        print " Page: "
        book_info.page=gets.chomp.to_i
        print "Year of publication:"
        year=gets.chomp.to_i
        print "Month of publication:"
        month=gets.chomp.to_i
        print "Date of publication:"
        day=gets.chomp.to_i
        book_info.publish_date=Date.new(year, month, day)

        # register one created collection of data in a database
        @d bh.do("insert into bookinfos values(
            \'#{key}\',
            \'#{book_info.title}\',
            \'#{book_info.author}\',
            \'#{book_info.page}\',
            \'#{book_info.publish_date}\"
        );")

        puts"\nRegistered successfully."
    end

    # display a list of collection data
    deflistAllBookInfos
        # hash table that changes the item name on the table to Japanese
        item_name={'id'=>"key", 'title'=>"book name", 'author'=>"author name", 'page'=>"page count", 'public_date'=>"date of publication"}

        puts "\n2.Viewing Library Data"
        print "View the library data."

        puts"\n-------------------"

        # read and display data from a table
        [email protected]("select*frombookinfos")

        # Take the results of the select statement one row at a time and repeat them
        counts = 0
        sth.each do | row |
            #row has one piece of data.
            # Use the each_with_name method to extract and display values and item names
            row.each_with_name do | val, name |
                # Display item names as Japanese item names
                puts"#{item_name[name]}:#{val.to_s}"
            end
            puts "-----------------"
            counts + = 1
        end

        # release the results of
        sth.finish

        "\n#{counts} displayed"
    end

    # Repeat process selection and post-selection processing
    def run
        while true
            # Display the function selection screen
            print"
            0. Initializing the library database
            1. Registration of collection data
            2. Display of collection data
            9. Closing
            Please select a number (0,1,2,9): "

            # wait for characters to be entered
            num=gets.chomp
            case
            when "0" == num
                # initialization of library database
                initBookInfos
            when "1" == num
                # Registration of collection data
                addBookInfo
            when"2" == num
                # Display of collection data
                listAllBookInfos
            when "9" == num
                # Terminate connection to database
                @dbh.disconnect
                # Application Termination
                puts "\nExit"
                break;
            else
                # Return to processing wait selection screen
            end
        end
    end
end

# This is where the application runs.
# Specify SQLite3 database for collection data
book_info_manager = BookInfoManager.new("bookinfo_sqlite.db")

# Repeat BookInfoManager process selection and post-selection processing
book_info_manager.run

C:/Ruby30-x64/lib/ruby/gems/3.0.0/gems/dbi-0.4.5/lib/dbi/handles/database.rb:238:in`=~':invalid byte sequence in UTF-8 (ArgumentError)
        from C: /Ruby30-x64/lib/ruby/gems/3.0.0/gems/dbi-0.4.5/lib/dbi/handles/database.rb:238:in`!~'
        from C: /Ruby30-x64/lib/ruby/gems/3.0.0/gems/dbi-0.4.5/lib/dbi/handles/database.rb:238:in`check_statement'
        from C: /Ruby30-x64/lib/ruby/gems/3.0.0/gems/dbi-0.4.5/lib/dbi/handles/database.rb:233:in `sanity_check'
        from C: /Ruby30-x64/lib/ruby/gems/3.0.0/gems/dbi-0.4.5/lib/dbi/handles/database.rb: 103:in `do'
        from ex2201.rb:90:in `addBookInfo'
        from ex2201.rb:152:in `run'
        from ex2201.rb:174:in `<main>'