一、別名

操作sql語句時給欄位起別名，別名和實體類屬性欄位一致

<select id="getUserList" resultType="User">
    select USER_ID as id,USER_NAME as name,USER_PASSWORD as password from user2 where USER_ID = #{id};
</select>

二、resultMap

使用mybatis配置檔案中配置resultMap進行欄位對映

<resultMap id="xxx" type="com.mybatis.domain.User">
    <id property="id" column="ID"></id>
    <result property="userName" column="USER_NAME"></result>
    <result property="password" column="PASSWORD"></result>
    <result property="userInformation" column="USER_INFORMATION"></result>
</resultMap>
 

使用@Result()和@ResultMap()註解
@Result()註解類似<resultMap id="resultField"></resultMap>
@ResultMap()註解類似<select id="queryUserList" resultMap="resultField"></select>
@ResultMap()可以讓多個介面使用@Result()中的欄位對映，注意@Result註解id和ResultMap註解中的value值一致

@Select({"select id,user_name,user_password,user_email,user_info,head_img,create_time from sys_user where id = #{id}"})
	@Results(id="userMap", value={
			@Result(column="id", property="id", id=true),
		    @Result(column="user_name", property="userName"),
		    @Result(column="user_password ", property="userPassword"),
		    @Result(column="user_email", property="userEmail"),
		    @Result(column="user_info", property="userInfo"),
		    @Result(column="head_img", property="headImg", jdbcType=JdbcType.BLOB),
		    @Result(column="create_time", property="createTime", jdbcType=JdbcType.TIMESTAMP)
	})
User selectUserById(Long id);
	
@Select({"select * from sys_user"})
@ResultMap("userMap")
List<User> queryUserList();
 

三、駝峰式命名

根據資料庫欄位名的下劃線實體類屬性欄位進行駝峰式命名

配置檔案中開啟駝峰轉換
yml配置

mybatis:
  configuration:
    map-underscore-to-camel-case: true #開啟資料庫欄位駝峰轉換

mybatis配置

<configuration>
<!--設定啟用資料庫欄位下劃線對映到java物件的駝峰式命名屬性，預設為false--> 
    <settings>
        <setting name="mapUnderscoreToCamelCase" value="true"/>
    </settings>
</configuration>