• Mongodb快速入门


    创建数据库

    使用数据库quickstart, 如果数据库不存在, 则创建数据库

    use quickstart
    

    插入数据

    db.students.insert({"name": "laggage", "age": 21})
    

    查找数据

    db.students.find()

    result:

    { "_id" : ObjectId("5f8aaeb8a2d37d24c77cea57"), "name" : "laggage", "age" : 21 }
    { "_id" : ObjectId("5f8aaf1fa2d37d24c77cea58"), "name" : "tom", "age" : 21 }
    { "_id" : ObjectId("5f8aaf32a2d37d24c77cea59"), "name" : "xixi", "age" : 21 }
    { "_id" : ObjectId("5f8aaf3da2d37d24c77cea5a"), "name" : "jack", "age" : 22 }
    

    查找年龄21的Student

    db.students.find({"age": 21})

    result:

    { "_id" : ObjectId("5f8aaeb8a2d37d24c77cea57"), "name" : "laggage", "age" : 21 }
    { "_id" : ObjectId("5f8aaf1fa2d37d24c77cea58"), "name" : "tom", "age" : 21 }
    { "_id" : ObjectId("5f8aaf32a2d37d24c77cea59"), "name" : "xixi", "age" : 21 }
    

    更新数据

    db.students.update({"name": "laggage"}, {$set: {"name": "laggage-updated"}})

    result:

    > db.students.find()
    { "_id" : ObjectId("5f8aaeb8a2d37d24c77cea57"), "name" : "laggage-updated", "age" : 21 }
    { "_id" : ObjectId("5f8aaf1fa2d37d24c77cea58"), "name" : "tom", "age" : 21 }
    { "_id" : ObjectId("5f8aaf32a2d37d24c77cea59"), "name" : "xixi", "age" : 21 }
    { "_id" : ObjectId("5f8aaf3da2d37d24c77cea5a"), "name" : "jack", "age" : 22 }
    

    删除数据

    删除 name 为 laggage-updated 的student

    db.students.remove({"name": "laggage-updated"})

    result:

    > db.students.remove({"name": "laggage-updated"})
    WriteResult({ "nRemoved" : 1 })
    > db.students.find()
    { "_id" : ObjectId("5f8aaf1fa2d37d24c77cea58"), "name" : "tom", "age" : 21 }
    { "_id" : ObjectId("5f8aaf32a2d37d24c77cea59"), "name" : "xixi", "age" : 21 }
    { "_id" : ObjectId("5f8aaf3da2d37d24c77cea5a"), "name" : "jack", "age" : 22 }
    

    dotnet中操作mongodb

    我的环境:

    win10 with powershell
    vs code with extensions ["vscode-solution-explorer", "C#"]

    创建控制台项目

    mkdir MongoWithDotnet ; cd MongoWithDotnet
    
    dotnet new sln -n MongoWithDotnet
    
    dotnet new console -n MongoWithDotnet
    
    dotnet sln .MongoWithDotnet.sln add .MongoWithDotnetMongoWithDotnet.csproj
    

    安装 MongoDB.Driver 包引用

    dotnet add .MongoWithDotnetMongoWithDotnet.csproj package MongoDB.Driver
    
    dotnet restore .MongoWithDotnetMongoWithDotnet.csproj
    

    简单的增删改查

    数据实体Student
    using MongoDB.Bson;
    using MongoDB.Bson.Serialization.Attributes;
    
    namespace MongoWithDotnet
    {
        public class Student
        {
            [BsonId]
            [BsonRepresentation(BsonType.ObjectId)]
            public string Id { get; set; }
    
            [BsonElement("name")]
            public string Name { get; set; }
    
            [BsonElement("age")]
            public uint Age { get; set; }
    
            public override string ToString()
            {
                return $"{Name}, {Age}岁";
            }
        }
    }
    
    mongodb增删改查
    using System;
    using System.Collections.Generic;
    using System.Linq;
    using MongoDB.Driver;
    
    namespace MongoWithDotnet
    {
        class Program
        {
            // 连接字符串
            public const string ConnectionString = "mongodb://<user nam,e>:<passoword>@localhost:27017/quickstart?authSource=admin";
    
            private MongoClient _client;
    
            public Program()
            {
                _client = new MongoClient(ConnectionString);
    
                var collection = _client.GetDatabase("quickstart").GetCollection<Student>("students");
    
                // 清空数据先
                var result = collection.DeleteMany(stu => true);
                Console.WriteLine($"Clear db, {result.DeletedCount} items deleted");
                
                // 准备测试数据
                collection.InsertMany(new Student[] {
                    new Student
                    {
                        Name = "tom",
                        Age = 21
                    },
                    new Student
                    {
                        Name = "lucy",
                        Age = 21
                    },
                    new Student
                    {
                        Name = "peipei",
                        Age = 25
                    },
                    new Student
                    {
                        Name = "tutu",
                        Age = 24
                    },
                    new Student
                    {
                        Name = "qiqi",
                        Age = 27
                    },
                });
    
                // 查询所有学生
                Console.WriteLine("All students:");
                DisplayStudents(collection.AsQueryable());
                Console.WriteLine("// --------- //");
                // --------- //
            
                // 查询年龄大于21的学生
                Console.WriteLine("Students whose age over 21:");
                DisplayStudents(collection.AsQueryable().Where(stu => stu.Age > 21));
                Console.WriteLine("// --------- //");
                // --------- //
    
                // 插入数据
                collection.InsertOne(new Student{ Name = "dotnet test user", Age = 23 });
                Console.WriteLine("All students:");
                DisplayStudents(collection.AsQueryable());
                Console.WriteLine("// --------- //");
                // --------- //
                
                // 修改名称为 dotnet test user 的学生
                var stu = collection.AsQueryable().FirstOrDefault(stu => stu.Name == "dotnet test user");
                stu.Name = "modified dotnet test user";
                stu.Age = 32;
                collection.ReplaceOne(s => s.Name == "dotnet test user", stu);
                Console.WriteLine("All students:");
                DisplayStudents(collection.AsQueryable());
                Console.WriteLine("// --------- //");
                // --------- //
    
                // 删除名称为 modified dotnet test user 的学生
                collection.DeleteOne(s => s.Name == "modified dotnet test user");
                Console.WriteLine("All students:");
                DisplayStudents(collection.AsQueryable());
                Console.WriteLine("// --------- //");
                // --------- //
            }
    
            private void DisplayStudents(IEnumerable<Student> students) => students.ToList().ForEach(stu => Console.WriteLine(stu));
    
            static void Main(string[] args)
            {
                new Program();
            }
        }
    }
    

    需要注意的是mongodb的每个数据库可以分别配置不同的用户名和密码, 如果要用admin数据库的用户名和密码登陆到其他数据库, 那么链接字符串需要制定authSource=admin, mongodb://<user nam,e>:<passoword>@localhost:27017/quickstart?authSource=admin

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  • 原文地址:https://www.cnblogs.com/Laggage/p/13871533.html
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