diff --git a/src/core/db/users/users.dto.ts b/src/core/db/users/users.dto.ts
new file mode 100644
index 0000000..ec9f493
--- /dev/null
+++ b/src/core/db/users/users.dto.ts
@@ -0,0 +1,59 @@
+// src/user/dto/create-user.dto.ts
+import { 
+  IsString, 
+  IsEmail, 
+  IsPhoneNumber, 
+  IsInt, 
+  Min, 
+  Max, 
+  IsOptional, 
+  Length, 
+  IsNotEmpty 
+} from 'class-validator'
+
+export class CreateUserDto {
+  // 用户名：必填、字符串、长度1-50
+  @IsString()
+  @IsNotEmpty({ message: '用户名不能为空' })
+  @Length(1, 50, { message: '用户名长度需在1-50字符之间' })
+  username: string;
+
+  // 邮箱：可选、合法邮箱格式
+  @IsOptional()
+  @IsEmail({}, { message: '邮箱格式不正确' })
+  email?: string;
+
+  // 手机号：可选、合法手机号格式（支持全球号码）
+  @IsOptional()
+  @IsPhoneNumber(null, { message: '手机号格式不正确' })
+  phone?: string;
+
+  // 密码哈希：可选（OAuth登录为空）
+  @IsOptional()
+  @IsString({ message: '密码哈希必须是字符串' })
+  password_hash?: string;
+
+  // 昵称：必填、字符串、长度1-50
+  @IsString()
+  @IsNotEmpty({ message: '昵称不能为空' })
+  @Length(1, 50, { message: '昵称长度需在1-50字符之间' })
+  nickname: string;
+
+  // GitHub ID：可选、字符串、长度1-100
+  @IsOptional()
+  @IsString({ message: 'GitHub ID必须是字符串' })
+  @Length(1, 100, { message: 'GitHub ID长度需在1-100字符之间' })
+  github_id?: string;
+
+  // 头像URL：可选、字符串
+  @IsOptional()
+  @IsString({ message: '头像URL必须是字符串' })
+  avatar_url?: string;
+
+  // 角色：可选、数字、1（普通）或9（管理员）
+  @IsOptional()
+  @IsInt({ message: '角色必须是数字' })
+  @Min(1, { message: '角色值最小为1' })
+  @Max(9, { message: '角色值最大为9' })
+  role?: number = 1; // 默认普通用户
+}
\ No newline at end of file
diff --git a/src/core/db/users/users.entity.ts b/src/core/db/users/users.entity.ts
new file mode 100644
index 0000000..a8a29b7
--- /dev/null
+++ b/src/core/db/users/users.entity.ts
@@ -0,0 +1,106 @@
+import { Entity, Column, PrimaryGeneratedColumn, CreateDateColumn, UpdateDateColumn } from 'typeorm';
+
+@Entity('users') // 对应数据库表名
+export class Users {
+  // id：bigint、主键、非空、唯一、自增
+  @PrimaryGeneratedColumn({
+    type: 'bigint',
+    comment: '主键ID'
+  })
+  id: bigint;
+
+  // username：varchar(50)、非空、唯一
+  @Column({
+    type: 'varchar',
+    length: 50,
+    nullable: false,
+    unique: true,
+    comment: '唯一用户名/登录名'
+  })
+  username: string;
+
+  // email：varchar(100)、允许空、唯一
+  @Column({
+    type: 'varchar',
+    length: 100,
+    nullable: true,
+    unique: true,
+    comment: '邮箱（用于找回/通知）'
+  })
+  email: string;
+
+  // phone：varchar(30)、允许空、唯一
+  @Column({
+    type: 'varchar',
+    length: 30,
+    nullable: true,
+    unique: true,
+    comment: '全球电话号码（用于找回/通知）'
+  })
+  phone: string;
+
+  // password_hash：varchar(255)、允许空
+  @Column({
+    type: 'varchar',
+    length: 255,
+    nullable: true,
+    comment: '密码哈希（OAuth登录为空）'
+  })
+  password_hash: string;
+
+  // nickname：varchar(50)、非空
+  @Column({
+    type: 'varchar',
+    length: 50,
+    nullable: false,
+    comment: '显示昵称（头顶显示）'
+  })
+  nickname: string;
+
+  // github_id：varchar(100)、允许空、唯一
+  @Column({
+    type: 'varchar',
+    length: 100,
+    nullable: true,
+    unique: true,
+    comment: 'GitHub OpenID（第三方登录用）'
+  })
+  github_id: string;
+
+  // avatar_url：varchar(255)、允许空
+  @Column({
+    type: 'varchar',
+    length: 255,
+    nullable: true,
+    comment: 'GitHub头像或自定义头像URL'
+  })
+  avatar_url: string;
+
+  // role：tinyint、非空、默认1
+  @Column({
+    type: 'tinyint',
+    nullable: false,
+    default: 1,
+    comment: '角色：1-普通，9-管理员'
+  })
+  role: number;
+
+  // created_at：datetime、非空、默认当前时间
+  @CreateDateColumn({
+    type: 'datetime',
+    nullable: false,
+    default: () => 'CURRENT_TIMESTAMP',
+    comment: '注册时间'
+  })
+  created_at: Date;
+
+  // updated_at：datetime、非空、默认当前时间
+  @UpdateDateColumn({
+    type: 'datetime',
+    nullable: false,
+    default: () => 'CURRENT_TIMESTAMP',
+    onUpdate: 'CURRENT_TIMESTAMP', // 数据库更新时自动刷新时间
+    comment: '更新时间'
+  })
+  updated_at: Date;
+}
\ No newline at end of file
diff --git a/src/core/db/users/users.module.ts b/src/core/db/users/users.module.ts
new file mode 100644
index 0000000..fef0d77
--- /dev/null
+++ b/src/core/db/users/users.module.ts
@@ -0,0 +1,26 @@
+/**
+ * 用户模块
+ * 
+ * 功能描述：
+ * - 整合用户相关的实体、服务和控制器
+ * - 配置TypeORM实体和Repository
+ * - 导出用户服务供其他模块使用
+ * 
+ * @author moyin
+ * @version 1.0.0
+ * @since 2024-12-17
+ */
+
+import { Module } from '@nestjs/common';
+import { TypeOrmModule } from '@nestjs/typeorm';
+import { Users } from './users.entity';
+import { UsersService } from './users.service';
+
+@Module({
+  imports: [
+    TypeOrmModule.forFeature([Users])
+  ],
+  providers: [UsersService],
+  exports: [UsersService, TypeOrmModule],
+})
+export class UsersModule {}
\ No newline at end of file
diff --git a/src/core/db/users/users.service.spec.ts b/src/core/db/users/users.service.spec.ts
new file mode 100644
index 0000000..b1f1f96
--- /dev/null
+++ b/src/core/db/users/users.service.spec.ts
@@ -0,0 +1,491 @@
+/**
+ * 用户实体、DTO和服务的完整测试套件
+ * 
+ * 功能：
+ * - 测试Users实体的结构和装饰器
+ * - 测试CreateUserDto的验证规则
+ * - 测试UsersService的所有CRUD操作
+ * - 验证数据类型和约束条件
+ * 
+ * @author moyin
+ * @version 1.0.0
+ * @since 2024-12-17
+ */
+
+import { Test, TestingModule } from '@nestjs/testing';
+import { getRepositoryToken } from '@nestjs/typeorm';
+import { Repository, DataSource } from 'typeorm';
+import { ConflictException, NotFoundException, BadRequestException } from '@nestjs/common';
+import { validate } from 'class-validator';
+import { plainToClass } from 'class-transformer';
+
+import { Users } from './users.entity';
+import { CreateUserDto } from './users.dto';
+import { UsersService } from './users.service';
+
+describe('Users Entity, DTO and Service Tests', () => {
+  let service: UsersService;
+  let repository: Repository<Users>;
+  let module: TestingModule;
+
+  // 模拟的Repository方法
+  const mockRepository = {
+    save: jest.fn(),
+    find: jest.fn(),
+    findOne: jest.fn(),
+    delete: jest.fn(),
+    softRemove: jest.fn(),
+    count: jest.fn(),
+    createQueryBuilder: jest.fn(),
+  };
+
+  // 测试数据
+  const mockUser: Users = {
+    id: BigInt(1),
+    username: 'testuser',
+    email: 'test@example.com',
+    phone: '+8613800138000',
+    password_hash: 'hashed_password',
+    nickname: '测试用户',
+    github_id: 'github_123',
+    avatar_url: 'https://example.com/avatar.jpg',
+    role: 1,
+    created_at: new Date(),
+    updated_at: new Date(),
+  };
+
+  const createUserDto: CreateUserDto = {
+    username: 'testuser',
+    email: 'test@example.com',
+    phone: '+8613800138000',
+    password_hash: 'hashed_password',
+    nickname: '测试用户',
+    github_id: 'github_123',
+    avatar_url: 'https://example.com/avatar.jpg',
+    role: 1
+  };
+
+  beforeEach(async () => {
+    module = await Test.createTestingModule({
+      providers: [
+        UsersService,
+        {
+          provide: getRepositoryToken(Users),
+          useValue: mockRepository,
+        },
+      ],
+    }).compile();
+
+    service = module.get<UsersService>(UsersService);
+    repository = module.get<Repository<Users>>(getRepositoryToken(Users));
+
+    // 清理所有mock
+    jest.clearAllMocks();
+  });
+
+  afterEach(async () => {
+    await module.close();
+  });
+
+  describe('Users Entity Tests', () => {
+    it('应该正确创建用户实体实例', () => {
+      const user = new Users();
+      user.username = 'testuser';
+      user.email = 'test@example.com';
+      user.phone = '+8613800138000';
+      user.password_hash = 'hashed_password';
+      user.nickname = '测试用户';
+      user.github_id = 'github_123';
+      user.avatar_url = 'https://example.com/avatar.jpg';
+      user.role = 1;
+      user.created_at = new Date();
+      user.updated_at = new Date();
+
+      expect(user.username).toBe('testuser');
+      expect(user.email).toBe('test@example.com');
+      expect(user.nickname).toBe('测试用户');
+      expect(user.role).toBe(1);
+    });
+
+    it('应该能够设置和获取所有属性', () => {
+      const user = new Users();
+      
+      // 验证可以设置和获取所有属性
+      user.username = 'testuser';
+      user.email = 'test@example.com';
+      user.phone = '+8613800138000';
+      user.password_hash = 'hashed_password';
+      user.nickname = '测试用户';
+      user.github_id = 'github_123';
+      user.avatar_url = 'https://example.com/avatar.jpg';
+      user.role = 1;
+      user.created_at = new Date();
+      user.updated_at = new Date();
+
+      expect(user.username).toBe('testuser');
+      expect(user.email).toBe('test@example.com');
+      expect(user.phone).toBe('+8613800138000');
+      expect(user.password_hash).toBe('hashed_password');
+      expect(user.nickname).toBe('测试用户');
+      expect(user.github_id).toBe('github_123');
+      expect(user.avatar_url).toBe('https://example.com/avatar.jpg');
+      expect(user.role).toBe(1);
+      expect(user.created_at).toBeInstanceOf(Date);
+      expect(user.updated_at).toBeInstanceOf(Date);
+    });
+  });
+
+  describe('CreateUserDto Validation Tests', () => {
+    it('应该通过有效数据的验证', async () => {
+      const validData = {
+        username: 'testuser',
+        email: 'test@example.com',
+        phone: '+8613800138000',
+        password_hash: 'hashed_password',
+        nickname: '测试用户',
+        github_id: 'github_123',
+        avatar_url: 'https://example.com/avatar.jpg',
+        role: 1
+      };
+
+      const dto = plainToClass(CreateUserDto, validData);
+      const errors = await validate(dto);
+
+      expect(errors).toHaveLength(0);
+    });
+
+    it('应该拒绝缺少必填字段的数据', async () => {
+      const invalidData = {
+        email: 'test@example.com'
+        // 缺少 username 和 nickname
+      };
+
+      const dto = plainToClass(CreateUserDto, invalidData);
+      const errors = await validate(dto);
+
+      expect(errors.length).toBeGreaterThan(0);
+      
+      const usernameError = errors.find(error => error.property === 'username');
+      const nicknameError = errors.find(error => error.property === 'nickname');
+      
+      expect(usernameError).toBeDefined();
+      expect(nicknameError).toBeDefined();
+    });
+
+    it('应该拒绝无效的邮箱格式', async () => {
+      const invalidData = {
+        username: 'testuser',
+        nickname: '测试用户',
+        email: 'invalid-email'
+      };
+
+      const dto = plainToClass(CreateUserDto, invalidData);
+      const errors = await validate(dto);
+
+      const emailError = errors.find(error => error.property === 'email');
+      expect(emailError).toBeDefined();
+    });
+
+    it('应该拒绝超长的用户名', async () => {
+      const invalidData = {
+        username: 'a'.repeat(51), // 超过50字符
+        nickname: '测试用户'
+      };
+
+      const dto = plainToClass(CreateUserDto, invalidData);
+      const errors = await validate(dto);
+
+      const usernameError = errors.find(error => error.property === 'username');
+      expect(usernameError).toBeDefined();
+    });
+
+    it('应该拒绝无效的角色值', async () => {
+      const invalidData = {
+        username: 'testuser',
+        nickname: '测试用户',
+        role: 10 // 超出1-9范围
+      };
+
+      const dto = plainToClass(CreateUserDto, invalidData);
+      const errors = await validate(dto);
+
+      const roleError = errors.find(error => error.property === 'role');
+      expect(roleError).toBeDefined();
+    });
+  });
+
+  describe('UsersService CRUD Tests', () => {
+
+    describe('create()', () => {
+      it('应该成功创建新用户', async () => {
+        mockRepository.findOne.mockResolvedValue(null); // 没有重复用户
+        mockRepository.save.mockResolvedValue(mockUser);
+
+        const result = await service.create(createUserDto);
+
+        expect(mockRepository.save).toHaveBeenCalled();
+        expect(result).toEqual(mockUser);
+      });
+
+      it('应该在用户名重复时抛出ConflictException', async () => {
+        mockRepository.findOne.mockResolvedValue(mockUser); // 模拟用户名已存在
+
+        await expect(service.create(createUserDto)).rejects.toThrow(ConflictException);
+        expect(mockRepository.save).not.toHaveBeenCalled();
+      });
+
+      it('应该在数据验证失败时抛出BadRequestException', async () => {
+        const invalidDto = { username: '', nickname: '' }; // 无效数据
+
+        await expect(service.create(invalidDto as CreateUserDto)).rejects.toThrow(BadRequestException);
+      });
+    });
+
+    describe('findAll()', () => {
+      it('应该返回用户列表', async () => {
+        const mockUsers = [mockUser];
+        mockRepository.find.mockResolvedValue(mockUsers);
+
+        const result = await service.findAll();
+
+        expect(mockRepository.find).toHaveBeenCalledWith({
+          take: 100,
+          skip: 0,
+          order: { created_at: 'DESC' }
+        });
+        expect(result).toEqual(mockUsers);
+      });
+
+      it('应该支持分页参数', async () => {
+        mockRepository.find.mockResolvedValue([]);
+
+        await service.findAll(50, 10);
+
+        expect(mockRepository.find).toHaveBeenCalledWith({
+          take: 50,
+          skip: 10,
+          order: { created_at: 'DESC' }
+        });
+      });
+    });
+
+    describe('findOne()', () => {
+      it('应该根据ID返回用户', async () => {
+        mockRepository.findOne.mockResolvedValue(mockUser);
+
+        const result = await service.findOne(BigInt(1));
+
+        expect(mockRepository.findOne).toHaveBeenCalledWith({
+          where: { id: BigInt(1) }
+        });
+        expect(result).toEqual(mockUser);
+      });
+
+      it('应该在用户不存在时抛出NotFoundException', async () => {
+        mockRepository.findOne.mockResolvedValue(null);
+
+        await expect(service.findOne(BigInt(999))).rejects.toThrow(NotFoundException);
+      });
+    });
+
+    describe('findByUsername()', () => {
+      it('应该根据用户名返回用户', async () => {
+        mockRepository.findOne.mockResolvedValue(mockUser);
+
+        const result = await service.findByUsername('testuser');
+
+        expect(mockRepository.findOne).toHaveBeenCalledWith({
+          where: { username: 'testuser' }
+        });
+        expect(result).toEqual(mockUser);
+      });
+
+      it('应该在用户不存在时返回null', async () => {
+        mockRepository.findOne.mockResolvedValue(null);
+
+        const result = await service.findByUsername('nonexistent');
+
+        expect(result).toBeNull();
+      });
+    });
+
+    describe('findByEmail()', () => {
+      it('应该根据邮箱返回用户', async () => {
+        mockRepository.findOne.mockResolvedValue(mockUser);
+
+        const result = await service.findByEmail('test@example.com');
+
+        expect(mockRepository.findOne).toHaveBeenCalledWith({
+          where: { email: 'test@example.com' }
+        });
+        expect(result).toEqual(mockUser);
+      });
+    });
+
+    describe('update()', () => {
+      it('应该成功更新用户信息', async () => {
+        const updatedUser = { ...mockUser, nickname: '更新后的昵称' };
+        
+        mockRepository.findOne
+          .mockResolvedValueOnce(mockUser) // findOne in update method
+          .mockResolvedValueOnce(null); // 检查昵称是否重复
+        mockRepository.save.mockResolvedValue(updatedUser);
+
+        const result = await service.update(BigInt(1), { nickname: '更新后的昵称' });
+
+        expect(mockRepository.save).toHaveBeenCalled();
+        expect(result.nickname).toBe('更新后的昵称');
+      });
+
+      it('应该在更新不存在的用户时抛出NotFoundException', async () => {
+        mockRepository.findOne.mockResolvedValue(null);
+
+        await expect(service.update(BigInt(999), { nickname: '新昵称' })).rejects.toThrow(NotFoundException);
+      });
+
+      it('应该在更新数据冲突时抛出ConflictException', async () => {
+        mockRepository.findOne
+          .mockResolvedValueOnce(mockUser) // 找到要更新的用户
+          .mockResolvedValueOnce(mockUser); // 发现用户名冲突
+
+        await expect(service.update(BigInt(1), { username: 'conflictuser' })).rejects.toThrow(ConflictException);
+      });
+    });
+
+    describe('remove()', () => {
+      it('应该成功删除用户', async () => {
+        mockRepository.findOne.mockResolvedValue(mockUser);
+        mockRepository.delete.mockResolvedValue({ affected: 1 });
+
+        const result = await service.remove(BigInt(1));
+
+        expect(mockRepository.delete).toHaveBeenCalledWith({ id: BigInt(1) });
+        expect(result.affected).toBe(1);
+        expect(result.message).toContain('成功删除');
+      });
+
+      it('应该在删除不存在的用户时抛出NotFoundException', async () => {
+        mockRepository.findOne.mockResolvedValue(null);
+
+        await expect(service.remove(BigInt(999))).rejects.toThrow(NotFoundException);
+      });
+    });
+
+    describe('count()', () => {
+      it('应该返回用户总数', async () => {
+        mockRepository.count.mockResolvedValue(10);
+
+        const result = await service.count();
+
+        expect(mockRepository.count).toHaveBeenCalled();
+        expect(result).toBe(10);
+      });
+    });
+
+    describe('exists()', () => {
+      it('应该在用户存在时返回true', async () => {
+        mockRepository.count.mockResolvedValue(1);
+
+        const result = await service.exists(BigInt(1));
+
+        expect(result).toBe(true);
+      });
+
+      it('应该在用户不存在时返回false', async () => {
+        mockRepository.count.mockResolvedValue(0);
+
+        const result = await service.exists(BigInt(999));
+
+        expect(result).toBe(false);
+      });
+    });
+
+    describe('search()', () => {
+      it('应该根据关键词搜索用户', async () => {
+        const mockQueryBuilder = {
+          where: jest.fn().mockReturnThis(),
+          orderBy: jest.fn().mockReturnThis(),
+          limit: jest.fn().mockReturnThis(),
+          getMany: jest.fn().mockResolvedValue([mockUser]),
+        };
+
+        mockRepository.createQueryBuilder.mockReturnValue(mockQueryBuilder);
+
+        const result = await service.search('test');
+
+        expect(mockRepository.createQueryBuilder).toHaveBeenCalledWith('user');
+        expect(mockQueryBuilder.where).toHaveBeenCalled();
+        expect(result).toEqual([mockUser]);
+      });
+    });
+
+    describe('findByRole()', () => {
+      it('应该根据角色查询用户', async () => {
+        mockRepository.find.mockResolvedValue([mockUser]);
+
+        const result = await service.findByRole(1);
+
+        expect(mockRepository.find).toHaveBeenCalledWith({
+          where: { role: 1 },
+          order: { created_at: 'DESC' }
+        });
+        expect(result).toEqual([mockUser]);
+      });
+    });
+  });
+
+  describe('Integration Tests', () => {
+    it('应该完成从DTO到Entity的完整流程', async () => {
+      // 1. 验证DTO
+      const dto = plainToClass(CreateUserDto, createUserDto);
+      const validationErrors = await validate(dto);
+      expect(validationErrors).toHaveLength(0);
+
+      // 2. 创建匹配的mock用户数据
+      const expectedUser = { ...mockUser, nickname: dto.nickname };
+      
+      // 3. 模拟服务创建用户
+      mockRepository.findOne.mockResolvedValue(null);
+      mockRepository.save.mockResolvedValue(expectedUser);
+
+      const result = await service.create(dto);
+
+      // 4. 验证结果
+      expect(result).toBeDefined();
+      expect(result.username).toBe(dto.username);
+      expect(result.nickname).toBe(dto.nickname);
+    });
+
+    it('应该正确处理可选字段', async () => {
+      const minimalDto: CreateUserDto = {
+        username: 'minimaluser',
+        nickname: '最小用户'
+      };
+
+      const dto = plainToClass(CreateUserDto, minimalDto);
+      const validationErrors = await validate(dto);
+      expect(validationErrors).toHaveLength(0);
+
+      // 验证可选字段的默认值处理
+      expect(dto.role).toBe(1); // 默认角色
+      expect(dto.email).toBeUndefined();
+      expect(dto.phone).toBeUndefined();
+    });
+  });
+
+  describe('Error Handling Tests', () => {
+    it('应该正确处理数据库连接错误', async () => {
+      mockRepository.save.mockRejectedValue(new Error('Database connection failed'));
+
+      await expect(service.create(createUserDto)).rejects.toThrow('Database connection failed');
+    });
+
+    it('应该正确处理并发创建冲突', async () => {
+      // 模拟并发情况：检查时不存在，保存时出现唯一约束错误
+      mockRepository.findOne.mockResolvedValue(null);
+      mockRepository.save.mockRejectedValue(new Error('Duplicate entry'));
+
+      await expect(service.create(createUserDto)).rejects.toThrow('Duplicate entry');
+    });
+  });
+});
\ No newline at end of file
diff --git a/src/core/db/users/users.service.ts b/src/core/db/users/users.service.ts
new file mode 100644
index 0000000..fb7fea3
--- /dev/null
+++ b/src/core/db/users/users.service.ts
@@ -0,0 +1,330 @@
+/**
+ * 用户服务类
+ * 
+ * 功能描述：
+ * - 提供用户的增删改查操作
+ * - 处理用户数据的业务逻辑
+ * - 数据验证和错误处理
+ * 
+ * @author moyin
+ * @version 1.0.0
+ * @since 2024-12-17
+ */
+
+import { Injectable, ConflictException, NotFoundException, BadRequestException } from '@nestjs/common';
+import { InjectRepository } from '@nestjs/typeorm';
+import { Repository, FindOptionsWhere } from 'typeorm';
+import { Users } from './users.entity';
+import { CreateUserDto } from './users.dto';
+import { validate } from 'class-validator';
+import { plainToClass } from 'class-transformer';
+
+@Injectable()
+export class UsersService {
+  constructor(
+    @InjectRepository(Users)
+    private readonly usersRepository: Repository<Users>,
+  ) {}
+
+  /**
+   * 创建新用户
+   * 
+   * @param createUserDto 创建用户的数据传输对象
+   * @returns 创建的用户实体
+   * @throws ConflictException 当用户名、邮箱或手机号已存在时
+   * @throws BadRequestException 当数据验证失败时
+   */
+  async create(createUserDto: CreateUserDto): Promise<Users> {
+    // 验证DTO
+    const dto = plainToClass(CreateUserDto, createUserDto);
+    const validationErrors = await validate(dto);
+    
+    if (validationErrors.length > 0) {
+      const errorMessages = validationErrors.map(error => 
+        Object.values(error.constraints || {}).join(', ')
+      ).join('; ');
+      throw new BadRequestException(`数据验证失败: ${errorMessages}`);
+    }
+
+    // 检查用户名是否已存在
+    if (createUserDto.username) {
+      const existingUser = await this.usersRepository.findOne({
+        where: { username: createUserDto.username }
+      });
+      if (existingUser) {
+        throw new ConflictException('用户名已存在');
+      }
+    }
+
+    // 检查邮箱是否已存在
+    if (createUserDto.email) {
+      const existingEmail = await this.usersRepository.findOne({
+        where: { email: createUserDto.email }
+      });
+      if (existingEmail) {
+        throw new ConflictException('邮箱已存在');
+      }
+    }
+
+    // 检查手机号是否已存在
+    if (createUserDto.phone) {
+      const existingPhone = await this.usersRepository.findOne({
+        where: { phone: createUserDto.phone }
+      });
+      if (existingPhone) {
+        throw new ConflictException('手机号已存在');
+      }
+    }
+
+    // 检查GitHub ID是否已存在
+    if (createUserDto.github_id) {
+      const existingGithub = await this.usersRepository.findOne({
+        where: { github_id: createUserDto.github_id }
+      });
+      if (existingGithub) {
+        throw new ConflictException('GitHub ID已存在');
+      }
+    }
+
+    // 创建用户实体
+    const user = new Users();
+    user.username = createUserDto.username;
+    user.email = createUserDto.email || null;
+    user.phone = createUserDto.phone || null;
+    user.password_hash = createUserDto.password_hash || null;
+    user.nickname = createUserDto.nickname;
+    user.github_id = createUserDto.github_id || null;
+    user.avatar_url = createUserDto.avatar_url || null;
+    user.role = createUserDto.role || 1;
+
+    // 保存到数据库
+    return await this.usersRepository.save(user);
+  }
+
+  /**
+   * 查询所有用户
+   * 
+   * @param limit 限制返回数量，默认100
+   * @param offset 偏移量，默认0
+   * @returns 用户列表
+   */
+  async findAll(limit: number = 100, offset: number = 0): Promise<Users[]> {
+    return await this.usersRepository.find({
+      take: limit,
+      skip: offset,
+      order: { created_at: 'DESC' }
+    });
+  }
+
+  /**
+   * 根据ID查询用户
+   * 
+   * @param id 用户ID
+   * @returns 用户实体
+   * @throws NotFoundException 当用户不存在时
+   */
+  async findOne(id: bigint): Promise<Users> {
+    const user = await this.usersRepository.findOne({
+      where: { id }
+    });
+
+    if (!user) {
+      throw new NotFoundException(`ID为 ${id} 的用户不存在`);
+    }
+
+    return user;
+  }
+
+  /**
+   * 根据用户名查询用户
+   * 
+   * @param username 用户名
+   * @returns 用户实体或null
+   */
+  async findByUsername(username: string): Promise<Users | null> {
+    return await this.usersRepository.findOne({
+      where: { username }
+    });
+  }
+
+  /**
+   * 根据邮箱查询用户
+   * 
+   * @param email 邮箱
+   * @returns 用户实体或null
+   */
+  async findByEmail(email: string): Promise<Users | null> {
+    return await this.usersRepository.findOne({
+      where: { email }
+    });
+  }
+
+  /**
+   * 根据GitHub ID查询用户
+   * 
+   * @param githubId GitHub ID
+   * @returns 用户实体或null
+   */
+  async findByGithubId(githubId: string): Promise<Users | null> {
+    return await this.usersRepository.findOne({
+      where: { github_id: githubId }
+    });
+  }
+
+  /**
+   * 更新用户信息
+   * 
+   * @param id 用户ID
+   * @param updateData 更新的数据
+   * @returns 更新后的用户实体
+   * @throws NotFoundException 当用户不存在时
+   * @throws ConflictException 当更新的数据与其他用户冲突时
+   */
+  async update(id: bigint, updateData: Partial<CreateUserDto>): Promise<Users> {
+    // 检查用户是否存在
+    const existingUser = await this.findOne(id);
+
+    // 检查更新数据的唯一性约束
+    if (updateData.username && updateData.username !== existingUser.username) {
+      const usernameExists = await this.usersRepository.findOne({
+        where: { username: updateData.username }
+      });
+      if (usernameExists) {
+        throw new ConflictException('用户名已存在');
+      }
+    }
+
+    if (updateData.email && updateData.email !== existingUser.email) {
+      const emailExists = await this.usersRepository.findOne({
+        where: { email: updateData.email }
+      });
+      if (emailExists) {
+        throw new ConflictException('邮箱已存在');
+      }
+    }
+
+    if (updateData.phone && updateData.phone !== existingUser.phone) {
+      const phoneExists = await this.usersRepository.findOne({
+        where: { phone: updateData.phone }
+      });
+      if (phoneExists) {
+        throw new ConflictException('手机号已存在');
+      }
+    }
+
+    if (updateData.github_id && updateData.github_id !== existingUser.github_id) {
+      const githubExists = await this.usersRepository.findOne({
+        where: { github_id: updateData.github_id }
+      });
+      if (githubExists) {
+        throw new ConflictException('GitHub ID已存在');
+      }
+    }
+
+    // 更新用户数据
+    Object.assign(existingUser, updateData);
+    
+    return await this.usersRepository.save(existingUser);
+  }
+
+  /**
+   * 删除用户
+   * 
+   * @param id 用户ID
+   * @returns 删除操作结果
+   * @throws NotFoundException 当用户不存在时
+   */
+  async remove(id: bigint): Promise<{ affected: number; message: string }> {
+    // 检查用户是否存在
+    await this.findOne(id);
+
+    // 执行删除 - 使用where条件来处理bigint类型
+    const result = await this.usersRepository.delete({ id });
+
+    return {
+      affected: result.affected || 0,
+      message: `成功删除ID为 ${id} 的用户`
+    };
+  }
+
+  /**
+   * 软删除用户（如果需要保留数据）
+   * 注意：需要在实体中添加 @DeleteDateColumn 装饰器
+   * 
+   * @param id 用户ID
+   * @returns 软删除操作结果
+   */
+  async softRemove(id: bigint): Promise<Users> {
+    const user = await this.findOne(id);
+    return await this.usersRepository.softRemove(user);
+  }
+
+  /**
+   * 统计用户数量
+   * 
+   * @param conditions 查询条件
+   * @returns 用户数量
+   */
+  async count(conditions?: FindOptionsWhere<Users>): Promise<number> {
+    return await this.usersRepository.count({ where: conditions });
+  }
+
+  /**
+   * 检查用户是否存在
+   * 
+   * @param id 用户ID
+   * @returns 是否存在
+   */
+  async exists(id: bigint): Promise<boolean> {
+    const count = await this.usersRepository.count({ where: { id } });
+    return count > 0;
+  }
+
+  /**
+   * 批量创建用户
+   * 
+   * @param createUserDtos 用户数据数组
+   * @returns 创建的用户列表
+   */
+  async createBatch(createUserDtos: CreateUserDto[]): Promise<Users[]> {
+    const users: Users[] = [];
+
+    for (const dto of createUserDtos) {
+      const user = await this.create(dto);
+      users.push(user);
+    }
+
+    return users;
+  }
+
+  /**
+   * 根据角色查询用户
+   * 
+   * @param role 角色值
+   * @returns 用户列表
+   */
+  async findByRole(role: number): Promise<Users[]> {
+    return await this.usersRepository.find({
+      where: { role },
+      order: { created_at: 'DESC' }
+    });
+  }
+
+  /**
+   * 搜索用户（根据用户名或昵称）
+   * 
+   * @param keyword 搜索关键词
+   * @param limit 限制数量
+   * @returns 用户列表
+   */
+  async search(keyword: string, limit: number = 20): Promise<Users[]> {
+    return await this.usersRepository
+      .createQueryBuilder('user')
+      .where('user.username LIKE :keyword OR user.nickname LIKE :keyword', {
+        keyword: `%${keyword}%`
+      })
+      .orderBy('user.created_at', 'DESC')
+      .limit(limit)
+      .getMany();
+  }
+}
\ No newline at end of file