日前从公司离职,很快,还没休息就步入了现在的公司,开始跟着公司的脚步走。
公司的项目基本都是大数据的,所以在数据库上大部分都是使用Mongodb和Redis,基本都是Nosql型的数据库为主。以前自己学着做过Mongodb和Redis的Demo,大体知道其怎么去运用,只是没有一个规范化的封装和运用,单纯是学习。现在有实战项目了,就激起了我前进学习的心,趁着今天自己查了下一些资料,学习了借鉴了一些前辈的方法后自己也封装了一个Mongdb的底层通用类,这里分享出来跟大家一起学习下。
这里主要是讲我封装的底层,不涉及到Mongodb的安装,启动,可视化查询等东西,后面会附上一些参考的地址供大家一起学习。
目前mongodb提供的驱动主要有两种:
1.官网驱动 下载地址:http://github.com/mongodb/mongo-csharp-driver/downloads
2.第三方的samus驱动 下载地址:https://github.com/samus/mongodb-csharp
两个驱动的运用自己都有使用过,个人感觉官方的驱动提供的方法比较多,用起来也比较顺手,而且更新度比samus的高,所以自己使用的是官方的驱动。
主要使用下面的两个dll
MongoDB.dll 驱动的主要程序
MongoDB.GridFS.dll 用于存储大文件。
基本的增删改查代码如下:
//数据库连接字符串 const string strconn = "mongodb://127.0.0.1:27017"; //数据库名称 const string dbName = "cnblogs"; //定义数据库 MongoDatabase db; /// <summary> /// 打开数据库链接 /// </summary> public void GetConnection() { //定义Mongo服务 Mongo mongo = new Mongo(strconn); //打开连接 mongo.Connect(); //获得数据库cnblogs,若不存在则自动创建 db = mongo.GetDatabase(dbName) as MongoDatabase; } /// <summary> /// 添加数据 /// </summary> public void Insert() { var col = db.GetCollection<Users>(); //或者 //var col = db.GetCollection("Users"); Users users = new Users(); users.Name = "xumingxiang"; users.Sex = "man"; col.Insert(users); } /// <summary> /// 更新数据 /// </summary> public void Update() { var col = db.GetCollection<Users>(); //查出Name值为xumingxiang的第一条记录 Users users = col.FindOne(x => x.Name == "xumingxiang"); //或者 //Users users = col.FindOne(new Document { { "Name", "xumingxiang" } }); users.Sex = "women"; col.Update(users, x => x.Sex == "man"); } /// <summary> /// 删除数据 /// </summary> public void Delete() { var col = db.GetCollection<Users>(); col.Remove(x => x.Sex == "man"); ////或者 ////查出Name值为xumingxiang的第一条记录 //Users users = col.FindOne(x => x.Sex == "man"); //col.Remove(users); } /// <summary> /// 查询数据 /// </summary> public void Query() { var col = db.GetCollection<Users>(); var query = new Document { { "Name", "xumingxiang" } }; //查询指定查询条件的全部数据 var result1 = col.Find(query); //查询指定查询条件的第一条数据 var result2 = col.FindOne(query); //查询全部集合里的数据 var result3 = col.FindAll(); }
1.数据库配置文件
考虑到一个项目里面可能使用到不同的数据库(比如:普通数据和文件数据等分别存到不同数据库中),也有可能会跨服务器查询,所以这里首先创建一个配置文件帮助类,主要是可以进行多个数据库配置,满足跨服务器,跨数据的需求。
配置格式如下:
<?xml version="1.0" encoding="utf-8" ?> <ServiceConfig> <mongodbs> <Item dbName="myDb" hostName="mongodb://127.0.0.1:27017"></Item> <Item dbName="myDb1" hostName="mongodb://127.0.0.1:27017"></Item> <Item dbName="myDb2" hostName="mongodb://127.0.0.1:27017"></Item> </mongodbs> </ServiceConfig>
Xml序列化对象类
public class ServiceConfig { [XmlArray, XmlArrayItem("Item")] public List<mongodbConfig> mongodbs { get; set; } } [XmlRoot] public class mongodbConfig { [XmlAttribute("dbName")] public string dbName { get; set; } [XmlAttribute("hostName")] public string hostName { get; set; } }
读取配置文件管理类
public class ManagerConfig { public static string ConfigPath; //加载配置文件 static ManagerConfig() { ConfigPath = "./config.xml"; } //xml序列化后的对象 private static ServiceConfig _settings; public static ServiceConfig ServiceSettings { get { return _settings ?? (_settings = Load()); } } //加载xml序列化为ServiceConfig对象 static ServiceConfig Load() { if (File.Exists(ConfigPath)) { using (FileStream fs = new FileStream(ConfigPath, FileMode.Open)) { XmlSerializer xs = new XmlSerializer(typeof(ServiceConfig)); //序列化为一个对象 _settings = (ServiceConfig)xs.Deserialize(fs); } } else { throw new Exception("数据库配置文件不存在,请检查"); //_settings = new ServiceConfig(); } return _settings; } }
2.实体通用接口
mongodb中本身没有自增ID的属性,自带有一个ObjectID,为了统一每个实体对象都有这个ID ,这里建立一个通用接口和一个底层实体基类来进行规范化处理
实体接口
public interface IMongoEntity { string Id { get; } }
底层实体基类
public class BaseModel : IMongoEntity { [BsonIgnore] public string Id { get { if (_id == ObjectId.Empty) _id = ObjectId.GenerateNewId(DateTime.Now); return _id.ToString(); } } [BsonId] private ObjectId _id; }
实体类的例子(继承于BaseModel类)
public class UserEntity : BaseModel { public string UserName { get; set; } public int Num { get; set; } //MongoDB中存储的时间是标准时间UTC +0:00 (相差了8个小时) [BsonDateTimeOptions(Kind = DateTimeKind.Local)] public DateTime PostTime { get; set; } }
3.Mongodb通用帮助基类 (主要类)
public class MongodbBase<T> where T : class,IMongoEntity { protected MongoServer server = null; protected MongoDatabase db = null; protected MongoCollection<T> collection; protected void Init(string DbName) { var Item = ManagerConfig.ServiceSettings.mongodbs.Where(p => p.dbName == DbName).FirstOrDefault(); if (Item == null) { throw new Exception("不存在数据库为: " + DbName + " 的配置对象,请检查"); } else { server = MongoDB.Driver.MongoServer.Create(Item.hostName); db = server.GetDatabase(Item.dbName); collection = db.GetCollection<T>(typeof(T).Name.Replace("Entity", "")); } } #region 查询 /// <summary> /// 根据ID获取对象 /// </summary> /// <param name="id"></param> /// <returns></returns> public T GetModelById(string id) { return collection.FindOneById(id); } /// <summary> /// 获取一条记录(自定义条件) /// </summary> /// <returns></returns> public T FirstOrDefault(Expression<Func<T, bool>> expression) { MongoDB.Driver.IMongoQuery query = Query<T>.Where(expression); return collection.FindOne(query); } /// <summary> /// 获取一条记录 /// </summary> /// <returns></returns> public T FirstOrDefault() { return collection.FindAll().FirstOrDefault(); } /// <summary> /// 获取全部 /// </summary> /// <returns></returns> public List<T> FindAll() { return collection.FindAll().ToList(); } /// <summary> /// 获取全部(自定义条件) /// </summary> /// <returns></returns> public List<T> FindAll(Expression<Func<T, bool>> expression) { MongoDB.Driver.IMongoQuery query = Query<T>.Where(expression); return collection.Find(query).ToList(); } /// <summary> /// 根据条件获取数量 /// </summary> /// <param name="expression"></param> /// <returns></returns> public long GetCount(Expression<Func<T, bool>> expression = null) { if (expression == null) { return collection.Count(); } else { return collection.Count(Query<T>.Where(expression)); } } /// <summary> /// 根据ID判断是否存在 /// </summary> /// <param name="id"></param> /// <returns></returns> public bool Exists(string id) { return collection.FindOneById(id) != null; } /// <summary> /// 分页 /// </summary> /// <param name="PageIndex">总页码</param> /// <param name="PageSize">页容量</param> /// <param name="RowCounts">总记录数</param> /// <param name="expression">条件</param> /// <param name="IsAsc">是否是正序</param> /// <param name="OrderFiled">排序的字段</param> /// <returns></returns> public List<T> Page(int PageIndex, int PageSize, out long RowCounts, Expression<Func<T, bool>> expression = null, bool IsAsc = true, params string[] OrderFiled) { MongoCursor<T> mongoCursor; //条件选择 if (expression != null) { RowCounts = collection.Find(Query<T>.Where(expression)).Count(); mongoCursor = collection.Find(Query<T>.Where(expression)); } else { RowCounts = collection.FindAll().Count(); mongoCursor = collection.FindAll(); } //排序 if (OrderFiled != null && OrderFiled.Length > 0) { //处理主键字段 for (int i = 0; i < OrderFiled.Length; i++) { if (OrderFiled[i].Equals("id", StringComparison.CurrentCultureIgnoreCase)) { OrderFiled[i] = "_id"; } } if (IsAsc) { mongoCursor = mongoCursor.SetSortOrder(SortBy.Ascending(OrderFiled)); } else { mongoCursor = mongoCursor.SetSortOrder(SortBy.Descending(OrderFiled)); } } return mongoCursor.SetSkip((PageIndex - 1) * PageSize).SetLimit(PageSize).ToList(); } #region 效率低,暂时不用 ///// <summary> ///// 分页 ///// </summary> ///// <returns></returns> //public List<T> Page(int PageIndex, int PageSize, out long RowCounts, Expression<Func<T, bool>> expression = null) //{ // List<T> ret = new List<T>(); // IQueryable<T> queryable; // //条件选择 // if (expression != null) // { // queryable = collection.Find(Query<T>.Where(expression)).AsQueryable(); // } // else // { // queryable = collection.FindAll().AsQueryable(); // } // RowCounts = queryable.Count(); // ret = queryable.Skip((PageIndex - 1) * PageSize).Take(PageSize).ToList(); // return ret; //} ///// <summary> ///// 分页 ///// </summary> ///// <typeparam name="TKey"></typeparam> ///// <param name="PageIndex"></param> ///// <param name="PageSize"></param> ///// <param name="RowCounts"></param> ///// <param name="expression"></param> ///// <param name="orderBy"></param> ///// <param name="IsOrder"></param> ///// <returns></returns> //public List<T> Page<TKey>(int PageIndex, int PageSize, out long RowCounts, Expression<Func<T, bool>> expression = null, Expression<Func<T, TKey>> orderBy = null, bool IsOrder = true) //{ // List<T> ret = new List<T>(); // IQueryable<T> queryable; // //条件选择 // if (expression != null) // { // queryable = collection.Find(Query<T>.Where(expression)).AsQueryable(); // } // else // { // queryable = collection.FindAll().AsQueryable(); // } // //排序 // if (orderBy != null) // { // if (IsOrder) // { // queryable = queryable.OrderBy(orderBy); // } // else // { // queryable = queryable.OrderByDescending(orderBy); // } // } // RowCounts = queryable.Count(); // ret = queryable.Skip((PageIndex - 1) * PageSize).Take(PageSize).ToList(); // return ret; //} #endregion #endregion #region 删除 /// <summary> /// 带条件的删除 /// </summary> /// <param name="expression"></param> /// <returns></returns> public void Delete(Expression<Func<T, bool>> expression) { MongoDB.Driver.IMongoQuery query = Query<T>.Where(expression); var result = collection.Remove(query); } /// <summary> /// 根据模型删除 /// </summary> /// <param name="model"></param> public void Delete(T model) { MongoDB.Driver.IMongoQuery query = Query<T>.Where(p => p.Id == model.Id); collection.Remove(query); } /// <summary> /// 根据ID删除 /// </summary> /// <param name="Id"></param> public void Delete(string Id) { MongoDB.Driver.IMongoQuery query = Query<T>.Where(p => p.Id == Id); collection.Remove(query); } /// <summary> /// 全部删除 /// </summary> /// <returns></returns> public void DeleteAll() { var result = collection.RemoveAll(); } #endregion #region 添加 /// <summary> /// 单模型添加 /// </summary> /// <param name="model"></param> /// <returns></returns> public void Insert(T model) { var result = collection.Insert<T>(model); } /// <summary> /// 批量添加 /// </summary> /// <param name="model"></param> /// <returns></returns> public void InsertBatch(List<T> model) { collection.InsertBatch<T>(model); } #endregion #region 修改 /// <summary> /// 修改 /// </summary> /// <param name="model"></param> /// <returns></returns> public void Update(T model) { var result = collection.Save<T>(model); } /// <summary> /// 批量修改 /// </summary> /// <param name="model"></param> public void UpdateAll(List<T> model) { model.ForEach(e => collection.Save<T>(e)); } #endregion }
4.业务类
当新建一个表(mongodb里面叫做集合),需要对其进行操作,包括一些业务处理时。首先继承MongodbBase类,然后使用Init方法初始化对象,如下面的UserServcices类
public class UserServices : MongodbBase<UserEntity> { public UserServices() { this.Init("myDb"); } }
5.使用
[TestClass] public class UnitTest1 { Random rd = new Random(); UserServices ubll = new UserServices(); #region 添加 [TestMethod] public void 添加() { UserEntity model = new UserEntity(); model.UserName = "Name" + rd.Next(100, 10000); model.Num = rd.Next(100, 10000); model.PostTime = DateTime.Now; ubll.Insert(model); } [TestMethod] public void 添加复杂模型() { ComplexEntity model = new ComplexEntity(); ComplexServices cbll = new ComplexServices(); model.Name = "Complex"; model.Schools = new List<School>(); model.Schools.Add(new School() { Master = new Grade() { Name = "Master" }, Name = "School", Students = new List<Student>() }); model.Schools[0].Students.Add(new Student() { Age = 22, Name = "张三" }); cbll.Insert(model); } [TestMethod] public void 批量添加() { List<UserEntity> Data = new List<UserEntity>(); for (int i = 0; i < 1000000; i++) { UserEntity model = new UserEntity(); model.UserName = "Name" + rd.Next(100, 10000); model.Num = rd.Next(100, 10000); model.PostTime = DateTime.Now; Data.Add(model); } ubll.InsertBatch(Data); } #endregion #region 修改 [TestMethod] public void 获取单个对象_修改() { var model = ubll.FirstOrDefault(p => p.Id != ""); model.UserName = "new1"; ubll.Update(model); } [TestMethod] public void 批量修改() { var model = ubll.FindAll(); for (int i = 0; i < model.Count; i++) { model[i].UserName = "Text"; } ubll.UpdateAll(model); } #endregion #region 查询 [TestMethod] public void 获取全部对象() { var model = ubll.FindAll(); var count = model.Count; } [TestMethod] public void 获取单个对象() { var model = ubll.FirstOrDefault(); var count = model.PostTime; } [TestMethod] public void 根据ID获取对象() { var model = ubll.GetModelById("eeef22d6-7ac6-40cd-9312-59ab15fd904a"); } [TestMethod] public void 获取全部对条件象_带条件() { var model = ubll.FindAll(p => p.UserName.Contains("Name")); var count = model.Count; } [TestMethod] public void 分页() { long Rows; List<UserEntity> pageDate = new List<UserEntity>(); pageDate = ubll.Page(300, 20, out Rows, p => p.Num > 1500); pageDate = ubll.Page(1, 20, out Rows, null, true, "Id"); pageDate = ubll.Page(1, 20, out Rows, null, true, "Num"); pageDate = ubll.Page(1, 20, out Rows, p => p.Num > 1500, false, "Id"); } [TestMethod] public void 获取数量() { //不带条件 var count = ubll.GetCount(); //带条件 var count1 = ubll.GetCount(p => p.Num > 5000); } #endregion #region 删除 [TestMethod] public void 删除_自定义条件() { ubll.Delete(p => p.Num >= 2000); } [TestMethod] public void 删除_删除模型() { var model = ubll.FirstOrDefault(); if (model != null) { ubll.Delete(model); } } [TestMethod] public void 删除_根据ID删除() { ubll.Delete("ec45ea8b-a551-46eb-ad58-1b4f5f2aab25"); } [TestMethod] public void 删除_删除全部() { ubll.DeleteAll(); } #endregion #region 其他 [TestMethod] public void 同时创建两个对象_同一数据库内() { LogServices Logbll = new LogServices(); UserEntity model = new UserEntity(); model.UserName = "Name" + rd.Next(100, 10000); model.Num = rd.Next(100, 10000); model.PostTime = DateTime.Now; ubll.Insert(model); LogEntity log = new LogEntity(); log.UserName1 = "Name" + rd.Next(100, 10000); log.Num1 = rd.Next(100, 10000); log.PostTime1 = DateTime.Now; Logbll.Insert(log); model.UserName = "Name" + rd.Next(100, 10000); model.Num = rd.Next(100, 10000); model.PostTime = DateTime.Now; ubll.Insert(model); } [TestMethod] public void 同时创建两个对象_不同一数据库内() { Log1Services Logbll = new Log1Services(); UserEntity model = new UserEntity(); model.UserName = "Name" + rd.Next(100, 10000); model.Num = rd.Next(100, 10000); model.PostTime = DateTime.Now; ubll.Insert(model); LogEntity log = new LogEntity(); log.UserName1 = "Name" + rd.Next(100, 10000); log.Num1 = rd.Next(100, 10000); log.PostTime1 = DateTime.Now; Logbll.Insert(log); model.UserName = "Name" + rd.Next(100, 10000); model.Num = rd.Next(100, 10000); model.PostTime = DateTime.Now; ubll.Insert(model); } [TestMethod] public void 当指定名称不存在时候() { ErrorServices error = new ErrorServices(); } #endregion }
以上就是自己封装的整体逻辑和代码,不过这里面还有一些不明白和不足的地方,这里提出来,希望大神们帮我解答下:
1.返回值问题
在添,删,改的使用,根据官网提供的驱动,都有一个WriteConcernResult对象返回,可是在测试中发现,这个返回的对象永远都是null
2.增加ID问题
mongodb中本身没有自增ID的属性,自带有一个ObjectID,如果我需要一个自增ID,是否是自己建一个ID属性,然后在增加的时候自己控制+1?不过这样是否性能上比较低,还要考虑多线程并发的情况下加锁的问题。所以不知道这块大家是怎么去实现的?
3.分页效率的问题
一开始分页我是先将结果转为Queryable,然后在进行操作,这个代码里面有这段,暂时注释掉了,后面再博客园上看到了一个前辈的mongodb分析后,改了下分页的方式,测试过很快,但在带条件获取记录行总数的时候,发现测试300W数据下,获取总数需要600ms的时间,不知道是我方法用错了还是有其他更好的?
最后附在几个学习的地址
mongodb入门:http://www.cnblogs.com/fish-li/archive/2011/06/26/2090800.html
官网驱动介绍:http://www.cnblogs.com/zhwl/p/3421034.html
分页优化参考:http://www.cnblogs.com/capqueen/p/MongoDBPagination.html
源码下载:戳这里-》