How do you configure mapping relationships using annotations in MyBatis?
In MyBatis, mapping relationships can be configured using annotations such as @Select, @Insert, @Update, @Delete for SQL statements, and @Results, @Result, @ResultMap for result mapping.
Here is an example of configuring mapping relationships using annotations:
@Mapper
public interface UserMapper {
@Select("SELECT * FROM users WHERE id = #{id}")
@Results({
@Result(property = "id", column = "id"),
@Result(property = "name", column = "name")
})
User getUserById(Long id);
@Insert("INSERT INTO users(id, name) VALUES(#{id}, #{name})")
void insertUser(User user);
@Update("UPDATE users SET name = #{name} WHERE id = #{id}")
void updateUser(User user);
@Delete("DELETE FROM users WHERE id = #{id}")
void deleteUser(Long id);
}
In the example above, SQL statements are configured using @Select, @Insert, @Update, @Delete annotations, and result mapping relationships are configured using @Results, @Result annotations. A UserMapper interface is defined, which includes methods for retrieving, inserting, updating, and deleting users, with the corresponding SQL statements and result mapping relationships configured through annotations.