Be Extra Careful about Pitfalls of MyBatis-Plus 2.x

What an Unreliable Lad You Are @TableField

Mybatis-Plus introduces many powerful annotations for us to indicate the mapping between entity properties and table fields. It's a great coding experience working with those annotations and IService relevant helper class. However, it's actually not true in Mybatis-Plus 2.x. Why? @TableField in 3.x could replace ResultMap fully, even applied in customized Mapper select statement like the example below.

package com.john.model;

@TableName("user")
public class User {
    @TableId
    private String id;
    @TableField("user_name")
    private String userName;
}

<mapper>
  <select id="getUsers" resultType="com.john.model.User">
    select * from user
  </select>
</mapper>

Believe me gentles, 2.x would let you down definitely. @TableField is out of work in above situation. What we have to do is declare the relations by ResultMap, or keep the entity property name as the same as the table field which is case-sensitive.

<mapper>
  <select id="getUsers" resultType="com.john.model.User">
    select id
           , user_name as userName
    from user
  </select>
</mapper>

The Pain I've Suffered from Pagination Plugin

Pagination plugin is another effective helper, but there are many differences between 3.x and 2.x. Listed as below.

Conclusion

If this post could give you a favor, it's my pleasure ?