MyBatis注解对应关系

Posted 2022-12-06 HC_Manage&

MyBatis注解对应关系

# crud
# 名称不一致
	@Select("select * from book where id = #id")
	@Results(
		@Result(property="id",column="id",id=true),
		@Result(property="name",column="b_name"),
		@Result(property="createTime",column="b_create_time"),
		@Result(property="price",column="price")
	)
	public Book findById(int id);

# 一对一
@Select("select * from chapter")
	@Results( 
		@Result(property = "id", column = "id",id=true),
		@Result(property = "name", column = "name"),
		@Result(property = "bookId", column = "book_id"),
		@Result(property = "book",column="book_id",one = @One(fetchType=FetchType.EAGER,select="com.zhiyou100.mapper.BookMapper.findById"))
	)
	public List<Chapter> findAll();

# 一对多
	@Select("select * from book")
	//解决数据库和java属性不一致
	//property:java属性
	//column:数据库属性
	//id:判断是否是主键
	@Results(
		@Result(property="id",column="id",id=true),
		@Result(property="name",column="b_name"),
		@Result(property="createTime",column="b_create_time"),
		@Result(property="price",column="price"),
		@Result(property="chapters",column="id",many=@Many(fetchType=FetchType.EAGER,select="com.zhiyou100.mapper.ChapterMapper.findByBookId"))
	)
	public List<Book> findAll();


# 多对多
	@Select("select * from user")
	@Results(
		@Result(property="id",column="id",id=true),
		@Result(property="roles",column="id",many=@Many(fetchType=FetchType.EAGER,select="com.zhiyou100.mapper.RoleMapper.findByUserId"))	
	)
	public List<User> findUserAndRole();
		@Select("SELECT * from role r INNER JOIN  user_role ur ON r.id = ur.role_id where ur.user_id = #userId")
	public List<Role> findByUserId(int userId);