STSDB 一

STSdb 4.0 是一个开源的NoSQL 数据库和虚拟文件系统，支持实时索引，完全用c#开发的。
引擎原理基于WaterfallTree（瀑布树）数据结构搭建

以下内容基于stsdb4.dll（4.0.3.0版本）库 ， 官方地址：http://stsdb.com/

using System;
using System.Collections.Generic;

namespace STSDB
{
    [Serializable]
    public class TStudent
    {
        public TStudent()
        {
        }
        public string Name { get; set; }
        public int Age { get; set; }
        public int GroupNumber { get; set; }
        public List<TCourse> CourseList { get; set; }
    }
}
using System;

namespace STSDB
{
    [Serializable]
    public class TCourse
    {
        public string CourseName { get; set; }
        public string Teacher { get; set; }
        public int Score { get; set; }
    }
}
演示代码：
/*
 * 1. STSdb 4.0 是一个开源的NoSQL 数据库和虚拟文件系统，支持实时索引，完全用c#开发的。
 * 引擎原理基于WaterfallTree（瀑布树）数据结构搭建
 * 
 * 
 * 2.特性
 * 支持几十亿级别的数据存取
 * 支持TB级别文件大小
 * 实时索引
 * 内置压缩
 * 内置序列化
 * 支持稀疏分散的文件（byte[]）
 * 存储内存可控
 * 支持多线程，且线程安全
 *  Storage  engine  instance  is  thread-safe.  Creating  (opening)  XTable  and  XFile  instances  in  one  storage  engine  from 
    different threads is thread-safe.
    XTable and XFile instances are also thread-safe. Manipulating different XTable/XFile instances from different threads 
    is thread-safe.
 * 
 * 3.缺点
 * 不支持事务
 * 同时处理所有打开的表
 * 
 * 支持多种情况下的数据引擎连接
   IStorageEngine engine = STSdb.FromMemory();              //从内存中读取
   IStorageEngine engine = STSdb.FromStream(stream);        //从数据流中读取
   IStorageEngine engine = STSdb.FromHeap(heap);            //从堆栈中读取
   IStorageEngine engine = STSdb.FromNetwork(host, port);   //从远程地址读取
  
 * 
 * 
 */

using System;
using System.IO;
using System.Linq;
using System.Collections.Generic;

namespace STSDB
{
    using Newtonsoft.Json;
    using STSdb4.Data;
    using STSdb4.Database;
    using STSdb4.Storage;
    using STSdb4.WaterfallTree;
    using STSdb4.Remote.Heap;

    class Program
    {
        static void Main(string[] args)
        {
            ExecuteCode(WriteData);
            ExecuteCode(ReadData);
            //ExecuteCode(DatabaseSchemeInfo);

            //ExecuteCode(ReadItem);
            //ExecuteCode(DeleteItems);
            //ExecuteCode(ReadItem);

            //ExecuteCode(GetRecord);
            //ExecuteCode(PageRecord);

            //ExecuteCode(Others);
            //ExecuteCode(ReNameTable);

            //ExecuteCode(ExistsTable);
            //ExecuteCode(DeleteTable);
            //ExecuteCode(ExistsTable);

            #region test
            //bool quit = false;
            //while (!quit)
            //{
            //    Console.Write("get item data: ");
            //    string demo = Console.ReadLine();
            //    switch (demo)
            //    {
            //        case "Y":
            //            break;
            //        case "Q":
            //            quit = true;
            //            break;
            //        default:
            //            Console.WriteLine("Choose a Word between Y and Q(to quit)");
            //            break;
            //    }
            //}
            #endregion

            Console.ReadKey();
        }
        /// <summary>执行方法</summary>
        static void ExecuteCode(Action act)
        {
            System.Diagnostics.Stopwatch stopwatch = new System.Diagnostics.Stopwatch();
            stopwatch.Start();

            act();

            stopwatch.Stop();
            TimeSpan timespan = stopwatch.Elapsed;

            Console.WriteLine("运行{0}秒", timespan.TotalSeconds);
        }

        /// <summary>
        /// 数据库名
        /// </summary>
        /// <remarks>文件名和扩展名不限制</remarks>
        protected static string DataBase = "ClassDB.db";
        /// <summary>
        /// 学生表名
        /// </summary>
        protected static string TableName = "tb_student";
        /// <summary>
        /// 【新】学生表名
        /// </summary>
        protected static string NewTableName = "new_tb_student";
        /// <summary>
        /// XFile
        /// </summary>
        protected static string XFileName = "tb_file";

        #region 基本操作
        /// <summary>
        /// 创建库，写入数据
        /// </summary>
        static void WriteData()
        {
            /*
             * ①：没有数据库会自动创建的，默认目录和应用程序目录一致；
             * ②：打开表，Key支持组合结构 => OpenXTable<TKey, TRecord>
             */
            using (IStorageEngine engine = STSdb.FromFile(DataBase)) //①
            {
                var table = engine.OpenXTable<int, TStudent>(TableName); //②
                //var table2 = engine.OpenXTable<TKey, TTick>("table2"); //支持key嵌套
                for (int i = 0; i < 1000; i++)
                {
                    table[i] = new TStudent
                    {
                        Name = "Jon_" + i.ToString(),
                        Age = new Random().Next(25, 30),
                        GroupNumber = i + (new Random().Next(310, 399)),
                        CourseList = new List<TCourse>()
                        {
                            new TCourse{
                                CourseName="C#高级编程"+i.ToString(),
                                Teacher="老陈"+i.ToString(), 
                                Score=80
                            },
                            new TCourse{
                                CourseName="C#函数式程序设计"+i.ToString(),
                                Teacher="老李"+i.ToString(),
                                Score=90
                            },
                            new TCourse{
                                CourseName="多线程实战应用"+i.ToString(),
                                Teacher="老张"+i.ToString(),
                                Score=95
                            },
                        }
                    };
                }
                engine.Commit();
            }
        }
        /// <summary>
        /// 读取数据
        /// </summary>
        static void ReadData()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase))
            {
                var table = engine.OpenXTable<int, TStudent>(TableName); //ITable:IEnumerable对象
                foreach (var item in table)
                    Console.WriteLine(JsonConvert.SerializeObject(item, Newtonsoft.Json.Formatting.Indented));

                Console.WriteLine(table.Count());   //TableName表中有100行数据
            }
        }

        /// <summary>
        /// 
        /// </summary>
        static void DatabaseSchemeInfo()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase)) //①
            {
                IDescriptor descriptor = engine[TableName];
                Console.WriteLine(descriptor.CreateTime.ToString("yyyy-MM-dd HH:mm:ss"));
                Console.WriteLine(descriptor.ModifiedTime.ToString("yyyy-MM-dd HH:mm:ss"));
                Console.WriteLine(descriptor.Name);
                //ID是表的唯一标识id，表一旦创建，它就创建了，后面只要表在就不会修改
                //重建表它会从新分配
                Console.WriteLine(descriptor.ID);

                //...
            }
        }

        /// <summary>
        /// 读取单条数据
        /// </summary>
        static void ReadItem()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase))
            {
                var table = engine.OpenXTable<int, TStudent>(TableName); //ITable: IEnumerable对象
                //var item = table.FirstOrDefault(x => x.Key <= 15 && x.Key >= 10);        //key是5的记录
                //table[10];
                var item = table.FirstOrDefault(x => x.Key == 5);        //key是5的记录
                if (item.Value != null)
                    Console.WriteLine(JsonConvert.SerializeObject(item, Newtonsoft.Json.Formatting.Indented));
                else
                    Console.WriteLine("key = 5 的记录不存在！");
                //Console.WriteLine("10<= key <= 15 的记录不存在！");
            }
        }

        static void AddItems()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase))
            {
                var table = engine.OpenXTable<int, TStudent>(TableName);
                //table[100] = new TStudent(){....};
                table.InsertOrIgnore(2, new TStudent());

                engine.Commit();
            }
        }

        /// <summary>
        /// 删除表数据
        /// </summary>
        static void DeleteItems()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase))
            {
                var table = engine.OpenXTable<int, TStudent>(TableName); //ITable:IEnumerable对象
                if (table != null)
                {
                    //table.Clear();          //清空表数据
                    table.Delete(5);        //删掉key是5的记录
                    //table.Delete(10, 15);  //删掉key从10到15的记录
                    engine.Commit();        //提交操作，不能少
                }
            }
        }

        /// <summary>
        /// 按需获取数据
        /// </summary>
        static void GetRecord()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase))
            {
                /*
                   Forward向前读取, Backward向后读取, 它们都有2个重载，下面重点说明第二个重载
                 * Forward(TKey from, bool hasFrom, TKey to, bool hasTo);
                 * Backward(TKey to, bool hasTo, TKey from, bool hasFrom);
                 * 超出范围的都不会排除，另外，查询范围超出也不会有影响,但是要注意一点，formkey和endkey的大小关系
                 * 
                 * 0<----------[(S)]----------------[(E)]------------->N
                 * 
                 */
                var table = engine.OpenXTable<int, TStudent>(TableName);
                var fiterTB = table.Forward(2, true, 9, true);    //索引从2到9
                //var fiterTB = table.Forward(2, false, 9, true);   //索引从0到9
                //var fiterTB = table.Forward(2, false, 9, false);  //索引从0到表结尾
                //var fiterTB = table.Forward(2, true, 9, false);   //索引从2到表结尾
                //Backward刚好相反
                foreach (var item in fiterTB)
                    Console.WriteLine(JsonConvert.SerializeObject(item, Newtonsoft.Json.Formatting.Indented));
            }
        }
        /// <summary>
        /// 数据分页
        /// </summary>
        static void PageRecord()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase))
            {
                int pageIndex = 2;
                int pageSize = 10;

                var table = engine.OpenXTable<int, TStudent>(TableName);
                var fiterTB = table.Skip(pageSize * (pageIndex - 1)).Take(pageSize);
                foreach (var item in fiterTB)
                    Console.WriteLine(JsonConvert.SerializeObject(item, Newtonsoft.Json.Formatting.Indented));
            }
        }
        /// <summary>
        /// 文件数和记录数
        /// </summary>
        static void Others()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase))
            {
                //表和虚拟文件的数量
                Console.WriteLine("数据库 " + DataBase + " 中有 {0} 张表：{1}", engine.Count, TableName);

                //表记录数
                var table = engine.OpenXTable<int, TStudent>(TableName);
                Console.WriteLine("表" + TableName + "中有" + table.Count() + "条记录");
            }
        }

        /// <summary>
        /// 表是否存在
        /// </summary>
        static void ExistsTable()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase))
            {
                //判断表存在与否
                //bool exists = engine.Exists(NewTableName);
                //Console.WriteLine(NewTableName + " exist?=>{0}", exists.ToString());

                bool exists = engine.Exists(TableName);
                Console.WriteLine(TableName + " exist?=>{0}", exists.ToString());
            }
        }

        /// <summary>
        /// 重命名表名
        /// </summary>
        static void ReNameTable()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase))
            {
                //判断表存在与否
                bool exists = engine.Exists(TableName);
                Console.WriteLine(TableName + " exist? =>{0}", exists.ToString());

                //表重命名
                engine.Rename(TableName, NewTableName);
                Console.WriteLine("表" + TableName + "被重命名为：" + NewTableName);

                if (engine.Exists(TableName))
                    Console.WriteLine("old table name "" + TableName + "" exist");
                if (engine.Exists(NewTableName))
                    Console.WriteLine("new table name "" + NewTableName + "" exist");
            }
        }
        /// <summary>
        /// 删除表
        /// </summary>
        static void DeleteTable()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase))
            {
                //删除表
                engine.Delete(TableName);
                //engine.Delete(NewTableName);
                engine.Commit();
            }
        }
        #endregion

        #region XFile

        static void TestXFile()
        {
            using (IStorageEngine engine = STSdb.FromFile(DataBase))
            {
                XFile file = engine.OpenXFile(XFileName);

                Random random = new Random();
                byte[] buffer = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

                for (int i = 0; i < 100; i++)
                {
                    long position = random.Next();

                    file.Seek(position, SeekOrigin.Begin);
                    file.Write(buffer, 0, buffer.Length);
                }
                engine.Commit();
            }
        }
        //XFile uses special XTable<long, byte[]> implementation to provide effective sparse file functionality.
        //One storage engine can have many files
        #endregion

        #region Client/Server

        static void ClientUpdateData()
        {
            using (IStorageEngine engine = STSdb.FromNetwork("localhost", 7182))
            {
                ITable<int, string> table = engine.OpenXTable<int, string>("table");
                for (int i = 0; i < 100000; i++)
                {
                    table[i] = i.ToString();
                }
                engine.Commit();
            }
        }

        static void ServerHandleData()
        {
            string _dbname = "test.stsdb4";
            using (IStorageEngine engine = STSdb.FromFile(_dbname))
            {
                var server = STSdb.CreateServer(engine, 7182);
                server.Start();
                //server is ready for connections
                //server.Stop();
            }
        }
        //The created server instance will listen on the specified port 
        //and receive/send data from/to the clients

        #endregion

        #region Memory Usage
        /*
         min/max children (branches) in each internal (non-leaf) node
         max operations in the root node
         min/max operations in each internal node
         min/max records in each leaf node
         number of cached nodes in the memory
         */
        static void MemoryUsageHandle()
        {
            using (StorageEngine engine = (StorageEngine)STSdb.FromFile(DataBase))
            {
                //下面的demo都是STS.DB的默认值设置

                //min/max children (branches) in each internal node
                engine.INTERNAL_NODE_MIN_BRANCHES = 2;
                engine.INTERNAL_NODE_MAX_BRANCHES = 4;
                //max operations in the root node
                engine.INTERNAL_NODE_MAX_OPERATIONS_IN_ROOT = 8 * 1024;
                //min/max operations in each internal node
                engine.INTERNAL_NODE_MIN_OPERATIONS = 64 * 1024;
                engine.INTERNAL_NODE_MAX_OPERATIONS = 128 * 1024;
                //min/max records in each leaf node
                engine.LEAF_NODE_MIN_RECORDS = 16 * 1024;
                engine.LEAF_NODE_MAX_RECORDS = 128 * 1024; //at least 2 x MIN_RECORDS
                //number of cached nodes in memory
                engine.CacheSize = 32;
            }
        }

        #endregion

        #region Heap

        /*using =>
            STSdb4.WaterfallTree;
            STSdb4.Storage;
            STSdb4.Remote.Heap;
        */
        static void HeaperEngine()
        {
            //Server端
            IHeap heap = new Heap(new FileStream("Heap.db", FileMode.OpenOrCreate));
            HeapServer server = new HeapServer(heap, 7183); //监听堆服务器
            server.Start(); //开始监听

            //从远程堆中创建 IStorageEngine 引擎，并处理数据
            //using (IStorageEngine engine = STSdb.FromHeap(new RemoteHeap("host", 7183)))
            //{
            //    ITable<int, string> table = engine.OpenXTable<int, string>("table");
            //    for (int i = 0; i < 100000; i++)
            //    {
            //        table[i] = i.ToString();
            //    }
            //    engine.Commit();
            //}
        }
        #endregion

        //...

    }
}