C#数据库在一个文件中

using System;
using System.Data.SQLite;

class Program
{
    static void Main()
    {
        string connectionString = "Data Source=mydb.db;Version=3;";

        using (SQLiteConnection connection = new SQLiteConnection(connectionString))
        {
            connection.Open();

            using (SQLiteCommand command = new SQLiteCommand(connection))
            {
                command.CommandText = "CREATE TABLE IF NOT EXISTS mytable (id INTEGER PRIMARY KEY, data TEXT);";
                command.ExecuteNonQuery();

                command.CommandText = "INSERT INTO mytable (data) VALUES ('Hello, world!');";
                command.ExecuteNonQuery();

                command.CommandText = "SELECT * FROM mytable;";
                using (SQLiteDataReader reader = command.ExecuteReader())
                {
                    while (reader.Read())
                    {
                        int id = reader.GetInt32(0);
                        string data = reader.GetString(1);
                        Console.WriteLine($"{id}: {data}");
                    }
                }
            }
        }
    }
}