MongoDB数据库：灵活高效的NoSQL数据存储解决方案

// 创建用户集合db.createCollection("users")// 添加用户db.users.insertMany([
  {
    userId: "U001",
    username: "alice",
    personalInfo: {
      firstName: "Alice",
      lastName: "Smith",
      birthDate: new Date("1990-05-15")
    },
    contact: {
      email: "alice@example.com",
      phone: "+8613800138000"
    },
    settings: {
      emailNotifications: true,
      smsNotifications: false
    },
    createdAt: new Date(),
    updatedAt: new Date()
  },
  {
    userId: "U002",
    username: "bob",
    personalInfo: {
      firstName: "Bob",
      lastName: "Johnson",
      birthDate: new Date("1985-08-20")
    },
    contact: {
      email: "bob@example.com",
      phone: "+8613800138001"
    },
    settings: {
      emailNotifications: false,
      smsNotifications: true
    },
    createdAt: new Date(),
    updatedAt: new Date()
  }])// 查询用户统计信息const userStats = db.users.aggregate([
  {
    $group: {
      _id: null,
      totalUsers: {$sum: 1},
      averageAge: {
        $avg: {
          $divide: [
            {$subtract: [new Date(), "$personalInfo.birthDate"]},
            365 * 24 * 60 * 60 * 1000  // 毫秒转换为年
          ]
        }
      }
    }
  }])// 更新用户信息db.users.updateOne(
  {userId: "U001"},
  {
    $set: {
      "contact.email": "alice.new@example.com",
      updatedAt: new Date()
    }
  })// 创建索引优化查询db.users.createIndex({"contact.email": 1})db.users.createIndex({"personalInfo.birthDate": 1})

安全性与性能优化

用户权限管理

// 创建管理员用户use admin
db.createUser({
  user: "admin",
  pwd: "securepassword",
  roles: ["root"]})// 创建应用用户use myapp
db.createUser({
  user: "appuser",
  pwd: "apppassword",
  roles: [
    {role: "readWrite", db: "myapp"},
    {role: "read", db: "reports"}
  ]})

// 查看数据库状态db.stats()// 查看集合状态db.users.stats()// 启用慢查询日志db.setProfilingLevel(1, 50)  // 记录超过50ms的查询